Specifications for. Hydraulic

Concrete Construction

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CONTENTS

Foreword.........................................................................................................................21 Scope...........................................................................................................................52 Quoted Standards.........................................................................................................63 General.........................................................................................................................94 Terms and Symbols....................................................................................................10

4.1 Terms..............................................................................................................10

4.2 Symbols...........................................................................................................12

5 Materials....................................................................................................................135.1 Cement............................................................................................................13

5.2 Aggregate........................................................................................................14

5.3 Admixtures......................................................................................................19

5.4 Additives.........................................................................................................20

5.5 Water...............................................................................................................22

6 Mix Proportion Selection............................................................................................237 Construction...............................................................................................................26

7.1 Mixing.............................................................................................................26

7.2 Transportation.................................................................................................27

7.3 Placement........................................................................................................30

7.4 Construction in rainy season............................................................................35

7.5 Curing.............................................................................................................37

8 Temperature Control...................................................................................................388.1 General............................................................................................................38

8.2 Temperature control measures.........................................................................39

8.3 Temperature measurement...............................................................................43

9 Construction in Low-Temperature Seasons................................................................449.1 General........................................................................................................44

9.2 Construction preparation............................................................................44

9.3 Construction method and heat-preservation measures................................46

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9.4 Temperature observation...............................................................................48

10 construction of embedded piece................................................................................5010.1 General.........................................................................................................50

10.2 Water-stop, expansion joint and drainage..................................................50

10.3 Cooling and joint grouting pipeline...........................................................54

10.4 Iron pieces.................................................................................................55

10.5 Interior observation devices..........................................................................56

11 Quality Control and Check............................................................................................5711.1 General........................................................................................................57

11.2 Quality control of raw materials..................................................................58

11.3 Control of concrete mixing and concrete mixture quality........................................60

11.4 Check and control of placement quality..........................................................61

11.5 Strength testing and evaluation.................................................................61

Appendix A (Normative Appendix) Calculation methods for average strength

standard deviation , strength assurance rate P and variation coefficient in one batch

.................................................................................................................................66

Appendix B (Informative Appendix) Calculation method of alkali content in concrete.......69Appendix C (Informative Appendix) Calculating early strength of concrete by maturity degree method................................................................................................................70Appendix D (Informative Appendix) Property indices of joint-sealing water-stop material........................................................................................................................74

2

Foreword

This specification is revised in accordance with "Notice of Establishing and Revising

Electric Power Industry Standard Program (the first plan) of 1996" (TC No. 40

[1996]), by Science and Technology Department of former Ministry of Electric Power.

Since the promulgation in April, 1982, SDJ 207-1982 Specification for Hydraulic

Concrete Construction (hereinafter is abbreviated as the "Original Standard"), has been

implemented for 19 years. It has brought good results to ensure the quality of hydraulic

concrete construction and to accelerate its technological development. With the recent

development of science and technology, the raised level of construction equipment, the

introduction foreign advanced technologies and changes of construction administrative

system, the original standard needs revision.

The revision work started from October, 1998. A special "revision group" was

established with the China Yangtze Three Gorges Engineering Development

Corporation acting main unit responsible for revision. Taking the full advantage of the

geographical location of the Three Gorges project construction site for which a large

number of hydropower construction, design and engineering supervision teams were

providing their service to the project, many experienced engineers and experts were

invited to meeting to collect comments, opinions and suggestions for the revision. Surveys

and data collection were conducted by the revision team staff specially sent out. As the

results, the first draft was finished in July 1999. In September of that year, experts were

invited to discuss and examine the first draft,

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which was revised for a second time based on the experts' comments and

suggestions. In November 1999, the questionnaire draft was finished, and the

approval draft was formed according to the collected comments and suggestions

once more in May 2000. In November 2000, the review conference on the

approval draft was held in Yichang. In August 2001, the approval submission

draft was finished. In accordance to the revision notice for the Hydraulic

Concrete Construction Specification and some revision comments for the Hydraulic

Concrete Construction standard issued by the department in charge, two chapters

"Concrete Formworks" and "Concrete Reinforcement Work", and one section

of the "Special Concrete Construction" are separated from the Original

Standard to form independent standards. Chapter one, four, five, six, seven and

Appendixes, of the original standard SDJ 207-1982 Hydraulic Concrete

Construction Specification are abolished.

According to specification DL/T 600_1996 General Rules for Draftingof

Electric Power Standard, three chapters are added, including the "Scope",

"Quoted Standards" and "Terms and Symbols". Some contents in Chapter 4

of the Original Standard, the concrete raw material, mix proportion selection,

concrete construction (including mixing, transportation, concrete placement,

concrete construction in raining season and concrete curing), as well as the

quality control and inspect are expanded to independent chapters. As a result,

there are altogether 11 chapters and 4 appendixes, together with the "General",

"Temperature Control", "Construction in Low Temperature Seasons",

"Construction of Embedded Pieces" of the original standard.

Appendix A of this specification is a normative appendix.

Appendixes B, C and D are informative appendixes.

This standard is proposed, managed and explained by Hydropower

Construction Standardization Technical Committee of the Electric

Power Industry.

Editing unit-in-chief of the Standard include the China Yangtze River

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Three Gorges Project Development Corporation and China Gezhouba Water

Resources and Hydropower Engineering Group.

Co-editing units of this standard are the Yangtze River Water

Resources Committee and the Fourth China Water Resources and

Hydropower Construction Bureau.

Main drafting persons are: Chen Fuhou, Zhou Hougui, She Zhenhuan, Liu

Wenyan, Liu Songbai, Zeng Guangyao, Zhang Xiaoting, Liu Yushan, Zhou

Shiming, Chen Guoqing, Hu Xing'e, Zhang Youming, Zhou Jun, Yan Sihai,

Xi Hao, Zhou Youlin, Li Baisheng, Sun Minglun.

Translated and examined by Sinohydro Corporation: Sun Hongshui,

Kang Minghua, Hu Jianwei, Jin Xiansong, Xiong Sizheng, Zhao Feng,

Wang Na, Dang Li.

5

1 Scope

This specification regulates the essential requirement for hydraulic

concrete construction. It applies for concrete and reinforced concrete

construction of hydraulic structures at grade 1, 2, 3 in large and middle-

scale hydropower and water resources projects.

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2 Quoted Standards

The following standards contain provisions which, through reference in this

text, constitute provisions of this standard. At time of publication, the editions

indicated are valid. All standards are subject to revision, and parties to agreements

based on this standard are encouraged to investigate the possibility of applying the

most recent editions of the standards indicated below.

GB 175-1999 Portland cement and ordinary portland cement GB/T 176-1996

Method for chemical analysis of cement

GB 200-1989 Moderate heat portland cement-Low heat port-land slag

cement

GB 748-1996 Sulfate resistance portland cement

GB/T 750-1992 Autoclave method for soundness of portland cement

GB 1344-1999 Portland blast furnace-slag cement, portland pozzolana cement

and Portland fly-ash cement

GB/T 1345-1991 Test method for fineness of cement —The 80gm sieve

GB/T 1346-2001 Test methods for water requirement of normal consistency, setting

time and soundness of the portland cements

GB/T 2022-1980 Test method for heat of hydration of cement (adiabatic

method)

GB/T 2059-2000 Strips of copper and copper alloys

GB/T 2847-1996 Pozzolanic materials used for cement production GB 2938-1997

Low heat expansive cement

GB 5749-1985 Sanitary standard for drinking water

GB/T 6645-1986 Granulated electric furnace phosphorous slag used for cement

production

GB 8076-1997 Concrete admixtures

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DL/T 5144 —

GB/T 9142-2000 Concrete mixers

GB 12573-1990 Sampling method of cement

GB/T 12959-1991 Test method for heat of hydration cement --The heat of

solution method

GB/T 14684-2001 Sand for building

GB/T 14685-2001 Pebble and crushed stone for building GB/T 17671-1999

Method of testing cements—Determination of strength

GB 50164-1992 Standard of quality control of concrete

GBJ 80 — 1985 Testing methods for the performance of ordinary

concrete

GBJ 107-1987 Inspection and evaluation of concrete strength

GBJ 119 -1988 Specifications application technology for concrete

additives

GBJ 146-1990 Technique of powdered coal ash concrete application

CECS 03: 1988 Technical specification for testing concrete strength by

coring method

CECS 38: 1992 Design and construction specification for steel fiber reinforced

concrete

DL 5017-1993 Specifications for manufacture installation and acceptance

of steel penstocks

DL/T 5055-1996 Technical standard of fly ash concrete for hydraulic

structures

DL/T 5057 — 1996 Design code for hydraulic concrete structures

DI 11. 5082 — 1998 Design specifications of hydraulic structures against ice and

freezing action

DL/T 5100-1999 Technical code for hydraulic concrete admixtures HG 2288-

1992 Rubber water-stop

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JGJ/T 10-1995 Technical specification for concrete mixture pumping in concrete

construction

JGJ 52-1992 Technical requirements and testing methods of sand for ordinary

concrete

JGJ 53-1992 Technical requirements and testing methods of gravel and crushed

stone for ordinary concrete

JGJ/T 55-1996 Specification for mix proportion design of ordinary concrete

JGJ 63-1989 Standard of water for concrete

JGJ 104-1997 Specification for building engineering winter construction

SD 105-1982 Testing specification for hydraulic concrete

SDJ 12-1978 Grade classification and design standard for water resources and

hydropower projects (mountain area and hilly area part)

SDJ 17-1978 Specification on investigation of natural building material for water

conservancy and hydropower engineering

SDJ 249.1-1988 Quality degree evaluation standard for unit engineering

work for water resources and hydropower capital construction

SDJ 336-1989 Technical specification for concrete dam safety monitoring (trial

application)

SDJ 338-1989 Specification for construction organization design of water

resources and hydropower projects (trial application) SL 62-1994 Construction

specification of cement grouting usedfor hydraulic structures

SL 172-1996 Technical code for construction of small hydropower station

SL 176-1996 Assessment specification for construction quality of hydraulic and

hydroelectric engineering (trial application)

ACI 211.1-1995 Standard methods for mix proportion selection of common

concrete, heavy weight concrete and mass concrete

ACI 214-1989 Recommended evaluating methods for concrete strength testing

results

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3 General

3.0.1 This specification specifies essential requirements to the

concrete raw materials, mix proportion selection, concrete mixture placement,

temperature control, placement in low-temperature seasons, installation of pre-

embedded pieces, quality control and check for concrete of hydraulic structures.

3.0.2 Hydraulic concrete shall meet the design requirements to resist

compression, tension, infiltration, freezing, cracking, eroding, grinding and corrosion.

3.0.3 Hydraulic concrete construction shall adopt up to date technique and

technologies, new materials and advanced equipments. A complete quality assurance

system shall be established.

3.0.4 Other concrete construction activities not included in this specification shall

be conducted in accordance with current relevant national standards and industrial

standards.

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4 Terms and Symbols

4.1 Terms

4 .1 .1 Admixtures

Under the admixtures the fly ash and other admixture materials are implied when

mixing cement-based concrete and mortar.

4. 1. 2 Strength grade

Compression strength grade of cubic samples under normative condition can be

classified as several grades.

4.1 .3 Water-binding ratio

Under the water-binding ratio, the water consumption per cubic meter of concrete to

binding material consumption is implied.

4.1 .4 Binding material consumption

Under binding material consumption the total mass of cement and binding material

in concrete per cubic meter is implied.

4.1.5 Mixing time

Under the mixing time duration from mixing all the materials to start up of mixture

disposal is implied.

4.1 .6 Concrete transportation time

Under the concrete transportation time, the time from unloading all the concrete

mixture from the mixer outlet to placing concrete mixture to the placement yard is

implied.

4.1.7 Concreting intermission time

Time intermission from finishing vibrating placed concrete mixture to placement of

upper concrete.

4. 1 .8 Rough surface

ocessed concrete surface without top milk and having slightly exposing grit.

4.1. 9 Concreting temperature

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Under the concreting temperature, the temperature in the depth of 10cm below

concrete surface, after concrete spreading and vibrating and before covering of upper

concrete is implied.

4.1.10 Suddenly drop in air temperature

Total accumulative dropping of daily average temperature more than 6°C during

two and three days.

4.1 .11 Cold wave

The sudden drop of temperature when the average temperature a day is below

5°C.

4 .1 .12 Maturity degree of concrete

The product of concrete curing time(h)and equivalent curing temperature

(°C) presented by mark "N".

4.1.1 3 Coefficient of superficial area

The ratio of the superficial area to volume of the structure presented by mark

"M".

4 . 1 .1 4 Severe cold region

The region whose lowest monthly average temperature is below –10°C.

4 . 1 .1 5 Cold region

The region whose lowest monthly average temperature is between –10°C

and –3°C.

4.1 .16 Mild region

The region whose lowest monthly average temperature is above –3 °C .

4 .1.1 7 Method of heat accumulation (regeneration method)

A construction method of adopting measure of heat preservation and

making use of quantity of heat by heating raw material and hydration heat of cement to guarantee normal increasing of concrete strength.

4.1.1 8 Comprehensive method of heat accumulationUnder the comprehensive method of heat accumulation, the "method of heat accumulation"

(regeneration method) complemented with the method of adding early strength additive or

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anti-freezing additive is implied.

4.2 Symbols

--Equivalent coefficient with the temperature at T

--Curing time with the temperature at T;

--Hydraulic concrete strength grade with design age of 90 days and

characteristic value of strength equaling 20MPa;

--Characteristic value of designed concrete strength;

--Strength of the mixed concrete;

--Average value of concrete strength;

--Standard deviation of concrete strength;

--Standard deviation of batch-acceptance concrete;

--Coefficient of variation of concrete strength;

--Coefficient of variation of concrete strength in hopper;

--Coefficient of variation of concrete strength of group i

-- Difference between maximum value and minimum

value among three samples of group i;

-- Minimum value of strength in group n;

F100--Anti-freeze grade of grade 100;

W2-- Anti-leakage grade of filtration resistance grade2

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5 Materials

5.1 Cement

5.1.1 It is proper to adopt one or two kinds of cement in every construction

project with specified suppliers.

5.1.2 Cement variety selection shall conform to the following principles:

1 For preparation of external concrete in water level fluctuation zone, concrete on

overflow surface and concrete in the water scouring part and concrete with anti-freezing

requirements, moderate-heat Portland cement or Portland cement should be selected, and

common Portland cement may be selected.

2 To prepare internal concrete, underwater concrete and foundation concrete, it

is appropriated to choose moderate-heat Portland cement, low-heat Portland blast

furnace slag cement, Portland blast furnace slag cement, Portland pozzolana cement,

Portland fly ash cement, common Portland cement and Low-heat expansive cement.

3 When the environment water is sulfate erosive, sulfate resistance Portland

cement shall be selected for use.

5.1.3 The strength grade of selected cement shall match designed strength grade of

concrete. For the concrete in water level fluctuation zone, concrete on overflow surface and

concrete at the water-scouring part and concrete with high anti-freeze requirements cement

of high strength grade shall be selected.

5.1.4 The selected cement shall conform to the stipulations in thecurrent national

standard. For particular requirements of construction, special requirements on the cement

chemical composition, mineral component and degree of fineness of cement shall be

proposed.

5.1.5 Each batch of cement sent to the construction site shall be attached with

certification and quality test report by manufacturer. The user shall conduct acceptance

inspection (Taking a set of sample from 200t to 400t cement provided by the same

manufacture for the cement of the same strength and grade. Those less than 200t can also

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be considered as one sampling unit) .

5.1.6 The inspection on cement quality shall be conducted in accordance with

the current national standard.

5.1.7 The transportation, preservation and use of cement shall obey the

following rules:

1 Bulk cement is preferential.

2 The cement sent to the site shall be stored separately in storage tanks or

storehouses with obvious symbols, according to marked sort, strength grade,

manufacturer and factory lot number.

3 In the process of transportation and storage, the cement shall be protected against

water and damp. The damp and lumped cement shall not be used until it is

certificated after processing and examination. The tank storing cement shall be

cleared once a month.

4 The cement storehouse shall be kept dry and equipped with water drainage and

ventilation facilities. If the bags of cement are piled up, damp check shall be set. The

bags shall be placed at least 30cm from the ground and the sidewall. The height of piles

shall not excess 15 bags, with space for transportation.

5 The tank-entry temperature should not be over 65°C for the hulk cement sent to

the site.

6 Use the cement first that is produced earlier. The storedcement shall

be check again for the storage time of cement in bag over three months or the

storage time of bulk cement over six months before using.

7 Prevent any lost and waste of cement and pay attention to environment.

5.2 Aggregate

5.2.1 Selection of the aggregate shall be based on the principle of good quality,

economy and using local materials. Either natural aggregate or artificial aggregate,

or both can be adopted. For artificial aggregate, limestone rock is preferential for

utilization if available.

5.2.2 When the quality and quantity of aggregate source changes, additional

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detailed investigation shall be made and content of alkali active component shall be

tested according to the current investigation specification for building material. The

use of alkali active aggregate is forbidden without special proof.

5.2.3 Technical and economic comparison shall be made based on total demand

quantity of coarse aggregate and fine aggregate in different construction periods, to

work reasonable plan for excavation and material usage, and to reduce material waste

as much as possible. Special dumping site shall be provided for surface layer

materials with proper environment protection measures to avoid soil erosion.

5.2.4 The processing technique of aggregates and equipment selection shall be

reasonable and reliable. Production capacity and storage capacity shall be

guaranteed to meet the requirements of concrete construction.

5.2.5 According to the actual requirements and conditions, the fine aggregate can be

divided into two sub-grades of the coarse and the fine and can be piled up into

storage separately. Two sub-grades ofthe fine aggregate shall be mixed into

concrete based on a certain ratio.

5.2.6 The storage and transportation of ready-made aggregates shall

conform to the following rules:

1 Storage site shall be equipped with effective drainage system.

When necessary, shed against sunshine and rain shall be built.

2 In the intervals between aggregate storage bins of different

aggregate grades, effective separation measure like partition shall be set.

Mixing of different grades is forbidden. Mixing of mud and other impurities

shall be also avoided.

3 Aggregate transportation times shall be limited as much as

possible. When unloading materials, descent slow-down control facility

shall be set, if the grain diameter of aggregate is over 40mm and its

freefall head is more than 3m.

4 The storage silo shall have adequate volume with the storage

height no less than 6m. The number and volume of the fine aggregate silo

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shall meet requirement of dehydration.

5 When taking material from store dump of ready-made coarse

aggregate, the same grade material shall be taken from different parts of

the storage place at the same time.

5. 2 .7 Quality requirements for fine aggregate (artificial sand, natural sand) are

as following:

1 The fine aggregate shall be hard, clean, and well graded. The

modulus of fineness of artificial sand shall be within the range of 2.4 to

2.8, and that of natural sand shall be within the range of 2.2 to 3.0. Tests

shall be made for extreme coarse or fine sand.

2 In the process of fine aggregate excavation, alkali activity test

shall be conducted regularly or according to the amount of excavation.

When there is any potential risk, necessary measures shall be adopted and

special test proof shall be arranged.

3 Water content in fine aggregate shall be kept stable. The water

content in saturation deficit of artificial sand shall not excess 6%. When it

is necessary, adopt measures to accelerate dewatering.

4 The other properties of fine aggregate shall conform to stipulations

in Table 5.2.7.

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5.2.8 Quality requirement for coarse aggregate (pebble and crushed

stone).

1 The maximum grain diameter of coarse aggregate shall not excess

two thirds (2/3) of the clear spacing of steel bars, one fourth (1/4) of the

minimum side length of element section and the half thickness of plain

concrete slab. For the concrete structures with a few or no steel bars, coarse

aggregate of large grain diameter is preferential.

2 In construction, it is appropriate to divide coarse aggregate into

following groups according to grain diameter:

1) For the maximum grain diameter of 40mm, divided into

D20 and D40 grades;

2) For the maximum grain diameter of 80mm, divided into

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D20, D40 and D80 grades;

3) For the maximum grain diameter of 150(120)mm, divided

into D20, D40, D80, D150(D120) grades.

3 Oversize and undersize aggregates shall be strictly controlled.

When the check is conducted with sieve size, the control standard is that

the oversize is less than 5 % and the undersize less than 10%. When the

check is conducted with sieving of oversize or undersize diameter, the

control standard is that the oversize is zero and the undersize is less than

2%.

4 Whether to adopt continuous grading or gap grading, this shall

be determined by tests.

5 Aggregates in various grades shall avoid separation. The

remained sieving quantity shall be between 40% and 70 % when using

square hole sieve of medium diameter (115mm, 60mm, 30mm,and

10mm) for the grade of D150, D80, D40 and D20.

6 When coarse aggregate containing reactive substances, rust and

lime nodules is used, special testing proof must be made.

7 The surface of coarse aggregate shall be clean. All grains coated with

powder or mud and dirty grains shall be eliminated.

8 The crushing index of crushed stone and pebble listed in Table 5.2.8-1 shall

be adopted.

Table 5.2.8-1 Crushing index of pebble and crushed stone

Aggregate sorts

Crushing index for different concretestrength grades%

C9055—C9040 ≤ C9035

Crushedstone

Sedimentary rock ≤10 ≤16

Metamorphic rockor plutonic igneousrocks

≤12 ≤C.20

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Igneous rocks ≤13 ≤30

Pebble ≤12 ≤516

9 Other properties of coarse aggregates shall meet the requirements listed in

Table 5.2.8-2.

Table 5.2.8-2 Quality requirements for coarse aggregates

Items Index RemarksContent of mud%

Size grade of D20, D40 ≤ 1Size grade of D80,D 150(D 120)

≤0.5

Content of clod UnacceptableFirmness Concrete with anti-freeze

requirement≤5

Concrete withoutanti-freeze requirement

≤512

Content of sulfide and sulfide%

≤0.5 Calculated into SO3 by mass

Table 5.2.8-2 (continue)

Items Index Remarks

Contents of organicBright than the standard color

When the aggregatecolorisdeeper thanthe

standard color, strength comparative test shall be conducted, with compressive

Apparent densitykg/m3

≥2550

Water absorbing capacity%

≤2.5

Flakiness content ≤15The content can beextended to 25 % through testing proof.5.2 .9 Sampling and testing methods shall be selected in accordance with the

SD 105 standard and relevant standards.

5.3 Admixtures

5.3.1 Adequate amount of admixtures shall be mixed into the hydraulic

concrete. The common admixtures include fly ash, tuff powder, slag micro-powder, silica

powder, granulated electric furnace phosphorous slag, magnesia and others. The kind and

the quantity of used admixtures shall be tested and selected in accordance with the

technical requirements of construction, the admixture properties and resources conditions.

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5.3.2 The qualities of admixtures shall conform to the current national standards

and relevant industry standards.

5.3.3 Fly ash admixture of grade 1 and grade 2 shall be selected.

5.3.4 Each delivery admixture shall attached with a product qualification

certificate, which contains manufacture, grade, date of ex-factory, lot number, quantity

and result of quality inspection and others.

5.3.5 The user shall make an acceptance inspection on the received admixture. For

the continually supplied admixture like fly ash, 200t is one lot (that below 200t is

considered also as one lot). For the continually supplied admixture like silica power,

20t is one lot (that less than 20t is considered also as one lot). For magnesium oxide

60t is considered as one lot (that less than 60t is considered also as one lot). The

quality inspection on admixture shall be conducted in accordance with the current

national standards and relevant industry standards.

5.3.6 Admixtures shall be stored in special store houses or storage tank. In the

process of transportation and storage, take measure to prevent moisture, litter and dust.

5.4 Additives

5.4.1 Proper quantity of additives must be mixed into hydraulic concrete.

5.4.2 Common additives include common water reducing agent, high-efficiency

water reducing agent, high-efficiency set-retarding and water reducing agent, set-

retarding and water-reducing agent, air-entraining water-reducing agent, set-

retarding agent, high- temperature set-retarding agent, air-entraining agent, pumping

agent and others. For special requirements, other additives can be also accepted. The

properties of selected additive must conform to the current national standards and

relevant industry standards.

5.4.3 Selection of additive shall be conducted according torequirements of

concrete properties, construction situation and compatibility tests with selected

concrete raw materials. The proper selection of additives and mixing quantity shall be

21

based on reliable proof and technical economic comparison. At the same construction site,

it is appropriate to choose one or two kinds of additives, which shall be supplied by

special manufacturer.

5.4.4 The concrete with anti-freeze requirement shall be mixed with air-

entraining agent. The air content of concrete shall be defined by testing according to

anti-freezing grade and maximum grain diameter of aggregate. The specifications listed

in table 5.4.4 can be regarded as reference.

Table 5.4.4 Air content of concrete mixed with air-entraining additive

Maximum grain diameter ofaggregate 20 40 80 150(120)mmAircontent%

≥F200 5.5 5.0 4.5 4.0

≤F150 4.5 4.0 3.5 3.0

Notes: Whether F150 concrete shall be mixed with air-entraining agent dependson the test results.

5.4.5 Additive shall be used after preparation into solution. When mixing solution,

the quantity shall be weighed accurately and the mixture shall be stirred evenly. For the

requirements of construction, additives may be in compound usage after testing proof.

When it is specified, they shall be prepared and used separately.

5.4.6 Each lot of delivery additive shall be attached with test report and

certificate. The using unit shall make acceptance inspection.

5.4.7 The lots of additives shall be divided by mixing quantities. 100t is

considered as one lot for the mixing quantity more than or equal to 1 %, 50t for the

mixing quantity less than or equal to 1 %,and It to 2t for the mixing quantity less than

or equal to 0.01 %. When the quantity of the lot is less than the specified amount, it is

regarded as one lot for testing and inspection.

5.4.8 Testing and inspection of additives shall be conducted in accordance with

current national standards and industry standards. 5.4.9 Additives shall be

appropriately stored in special storage house or at designated place, with marks for

different admixtures in respective separate storage. Special attention shall be paid to

protect power additives against water and moistures. When additives are stored for a

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long period with suspect properties, they must be tested and rechecked.

5.5 Water

5.5.1 The drinking water conforming to the national standard can be used to

prepare and cure concrete. Any untreated industrial waste water or domestic sewage shall

not be used to mix and cure concrete. 5.5 .2 The surface water, ground water and other

sorts of water shall be tested according to current relevant standards, when it is used to

prepare and cure concrete for the first time. Testing items and standards shall be in

accordance with following requirements:

1 The difference of initial setting time and different of final setting time between

the standard drinking water and the water above for concrete mixing and curing shall not

be over 30min.

2 Compressive strength of cement mortar prepared, with water to be tested at age

28 days shall not be less than that of mortar mixed with standard water by 90%.

3 The pH value and content of undissolved substances, dissolved substances,

chloride and sulphate in water to be used to prepared and cure concrete shall be in

accordance with stipulations isted in Table 5.5.2.

Table 5.5.2 Index requirements of water used

for concrete preparation and curing

ItemsReinforced

concretePlain

concreteItems

Reinforced concrete

Plainconcrete

pH value >4 >4Chloride (in Cl)

mg/L<1200 <3500

lJn-dissolvedsubstances

mg/L<2000 <5000

Sulfate(in SO4 )mg/L

<2700 <2700

Dissolvedsubstance

mg/L<5000 <10000

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6 Mix Proportion Selection

6.0.1 In order to meet the requirements of concrete design strength, durability,

impermeability as well as the construction requirement on workability, optimal selection of

concrete mix proportion shall be carried out. With comprehensive analysis and comparison,

the mixing proportion selection of concrete construction shall result in a reasonable

reduction of cement consumption. The concrete mix proportion selection for main

structures shall be finalized with detailed examination.

6.0.2 Concrete design strength

1 The concrete design strength shall be calculated with the following formula:

fcu,0= fcu,k+tσ (6.0.2-1)

Where: fcu,0-concrete design strength, MPa;

fcu,k--standard value of concrete strength at design age, MPa;

t--probability coefficient, selected by probability rate P please refer to the

values in Table Al of Appendix A;

σ--standard deviation of concrete strength, MPa.

2 Standard deviation of concrete strength (σ) is defined according stipulations as

follows:

1) When the recent data of concrete strength of the same sort is

unavailable, refer σcan be selected from Table 6.0.2.

Table 6.0.2 Value of standard deviationσ

Standard valueof concrete strength

≤C9015C9020— C9025C9030— C9035C9040— C9045≥C9050

σ(90d) MPa 3.5 4.0 4.5 5.0 5.5

2) When the data obtained from last month (or three months) of concrete

24

strength of the same strength grade and mixing proportion, standard

deviation of concrete strength (σ) shall be calculated with the

following formula:

(6.0.2-2)

Where: --specimen strength of group i, MPa;

--average strength of specimen of n groups, MPa;

n--number of specimen units, n shall be over 30.

Lower limit value of o-: For the concrete with the design strength below or equal

to that of the grade C9025, when o• is calculated to be less than 2.5MPa, the value of cr

can be taken as 2.5MPa; for the concrete with the design strength over or equal to grade

C9030, when a is calculated less than 3.0MPa, the value of a- can be taken as

3 .0MPa.

In the process of construction a dynamic type control shall be conducted to

adjust the value of a according to the statistical concrete strength results.

6.0.3 Standard value of the concrete design strength in MPa, is defined as the

standard value of concrete strength at design age and expressed with the compressive

strength of cubic specimen of 150mm by side length which is prepared and cured with

standard method.

6.0.4 Quantity of the binding material used for the internal mass concrete should

not less than 140kg/m3. The content of cement clinker should not less than 70kg/m3.

6.0.5 The water-binding ratio (or water-cement ratio) of concrete shall be

determined by testing according to the design requirements for concrete properties and

shall not excess the stipulations in Table 6.0.5.

Table 6.0.5 Maximum allowable value of water-binding ratio

Position Extremely cold area

Cold area

Warm area

25

Above up & downstream water level (external dam body)

0.50 0.55 0.60

Zone of water level fluctuations (external dam body)

0.45 0.50

Below lowest water level of up & downstream (external dam body)

0.50 0.55 0.60

Foundation 0.50 0.55 0.60Internal area 0.60 0.65 0.65Position washed by water flow 0.45 0.50 0.50Notes: Under erosive water, the maximum allowable water-binding ratio (or water-cement ratio) for the concrete at water level fluctuation zone and the submerged concrete shall be reduced by 0.05.6.0.6 Graduation of the coarse aggregate and selection of the sand content shall be

comprehensively analyzed and defined through tests in accordance with the

requirements of concrete and the requirements for concrete construction workability and

minimum unit water consumption, combined with the balanced aggregate production.

6.0.7 The concrete slump shall be determined according to structure

section of building, steel bars content, distance of transportation, placement

method, means of transportation, vibrating capacity and climate conditions. When

selecting the concrete mixing proportion, it is proper to make comprehensive

consideration and adopt low slump. The slump value of the concrete mixture at the

concrete placement site can be selected with reference to the Table 6.0.7.

Table 6.0.7 Concrete slump at concrete placement site

Concrete variety_

Slumpcm

Concrete variety Slumpcm

Plain concrete or less Reinforced concretereinforced concrete 1~4 with reinforcement ratio over 1% 5~9

Reinforced concretewith reinforcement ratio not over 1%

3~6

Notes: When there temperature control requirements for the concrete placementor the concrete is placed in high or low temperature seasons, the slump

can be properly increased or reduced according to actual conditions.6.0.8 When the aggregate with alkali reactivity is used, the total alkali

content in concrete shall be strictly controlled for mix proportion selection to

guarantee the durability of concrete. The calculating method of alkali content in

concrete is given in AppendixB.

6.0.9 The method of concrete proportion design and concrete tests shall be adopted

in accordance with SD 105 — 1982 Testing Specification for Hydraulic Concrete.

26

24

The anti-freezing characteristic shall be defined by the quick-frozen test.

7 Construction

7.1 Mixing

7.1.1 Before concrete production, the mixing equipment shall be tested for the

best charging sequence and mixing time according to the approved concrete mix

proportions.

7.1 .2 The ingredient mixing shall be made based on the approved list of the

concrete mix proportions. It is forbidden to make any arbitrary alteration.

7.1.3 The mixture amount of concrete ingredient materials shall be weighed. The

allowable weighing error shall not exceed the value in Table 7.1.3.

Table 7.1.3 Allowable weighing error of concrete mixture materials

MixtureAllowable

weighing error%

MixtureAllowable

weighing error%Cement, admixtures, water,

ice, additive solution±1 Aggregate ±2

7.1.4 Concrete mixing time shall be determined by testing. The minimum

mixing time listed in Table 7.1.4 may be adopted.

Table 7.1.4 Minimum concrete mixing time

Volume of mixer Qm3

Maximumgrain diameterof aggregate

Minimum mixing times

Self-dropping mixer Forcing mixer

0.8.≤Q≤1 80 90 60

Volume of mixer Qm3

Maximumgrain diameterof aggregate

Minimum mixing times

Self-dropping mixer Forcing mixer

1 <Q,<-3 150 120 75Q>3 150 150 90

Notes: 1 Mixing amount in mixer shall be no more than the rated capacity ofmixer by 110%.

2 The mixing time of iced concrete shall be prolonged by 30s (15s inthe forcing mixer). The concrete mixture out of mixer shall not

contain ice.

27

7.1 .5 Before each shift, the wearing state of mixer blades shall be checked. In the

process of mixing concrete, the water content of aggregate shall be checked regularly.

When necessary, the aggregate water content shall be measured more frequently.

7.1.6 Dry mixing method is suitable for adding the concrete additives at site,

and the concrete mixture must be ensured to be mixed evenly.

7 . 1 .7 The water content in the additive solution shall be deducted 1rom that for

the concrete mixing.

7.1.8 After the second screening at the concrete batching plant, the oversize and

undersize particle content of the coarse aggregate shall he controlled within the

required range.

7.1.9 The concrete mixture shall be regarding as unqualified mixture when

one of the following occasions occurs:

1 There is no remedy because of the misused concrete mix proportion list and the

resulted concrete mixture can not meet the duality requirements;

2 When concrete ingredient materials are proportioned formixing, one of the

ingredient materials is out of control in weighing or missed in feeding, so that the

resulted concrete mixture does not meet the quality requirement;

3 Uneven mixing or mixed with green material;

4 Concrete slump at the mixer outlet excesses the maximum permissible value.

7.2 Transportation

7.2.1 The concrete transportation equipment and its capacity shall be matched to

the concrete mixing capacity, concrete placement capacity and the concrete placement

surface.

7.2.2 The transportation equipment shall prevent the concrete from separation,

mortar leakage, serious bleeding, excessive temperature upturn and slump loss.

7.2.3 Clear distinctive marks shall be used when transporting concrete with two

or more strength grades, grading or other different properties.

7.2.4 In concrete transporting, the transporting time and the transporting

transition times shall be reduced as much as possible. The transporting time of

28

concrete mixed with common water reducing agent shall not excess the values

specified in Table 7.2.4. When the concrete starts initial setting or losses its plasticity,

it shall be regarded as waste material. It is forbidden to add water in the process of

concrete transporting and unloading.

Table 7.2.4 Time of concrete transportation

Average temperature°C

Time min

20-30 45Average temperature

°CTime min

10-20 605-10 90

7.2.5 At high or low temperature conditions the equipment of concrete

transportation shall be covered or protected with insulation measure to avoid any negative

effect on concrete caused by weather And air temperature.

7.2.6 The free-dropping height of concrete shall not be over 1.5m. When this height

is exceeded, the descent control measures or other measures shall be adopted to avoid

aggregate separation.

7.2.7 When trucks, side tipping wagons, side dumping trucks, transfer car, transit

mixer and other special vehicles are used for the concrete transportation, the following

stipulations shall be followed:

1 The vehicles shall be assigned only for this use. The roads for concrete

transportation shall be maintained smooth.

2 The thickness of loaded concrete shall not less than 40cm, and the wagon box

shall be smooth and sealed without mortar leaking.

3 The concrete shall be fully unloaded every time and the wagon box (wagon

container) shall be cleaned regularly.

4 When the concrete is placed directly by transportation vehicles, the measures

to guarantee the concrete construction quality must be adopted.

7.2.8 When lifting concrete with gantry crane, tower crane, cable crane, and

other cranes, the following specifications shall be conformed

1 The crane parts like drop hanger, hoisting cable, auxiliary facilities of

29

electromechanical system, lifting lug and discharge hole of hoist bucket shall be

checked and maintained timely to keep the equipment normally operation.

2 To ensure the hoist bucket not leaking mortar and clean it frequently.

3 During crane operation, attention shall be paid to its distance and height from the

surrounding construction equipments.

7.2.9 When transporting concrete with belt conveyor machines (including tower

belt conveyor, tire belt, and so on), the following regulations shall be conformed.

1 Mortar losses in the course of concrete transporting shall be avoided. When

necessary, the sand content in the mix proportion shall be increased adequately.

2 For transportation of the concrete with the maximum particle diameter of aggregate

over 80mm, compatibility tests with the type of equipment and transportation methods shall

be carried out to meet the quality requirements of concrete.

3 Baffle plate, discharging guide tube and scratch board at the discharging part of

the belt machine shall be set up.

4 The material disposal by belt machine shall be well distributed. The

height of stockpiles shall be less than lm.

5 Washing equipment shall be installed to wash the cement mortar residue adhered

to the surface of belt, and the washing water shall not flow onto the concrete placement

surface.

6 Covering sheds shall be built over the open-air belt machine to prevent from

the effect by sunshine, wind and rain. For construction in low-temperature season,

appropriate heat protection measures shall be taken.

7 .2 .10 When transporting concrete with sliding tube, hose pipe, chute,

and negative-pressure (vacuum) chute, the following regulationsshall

beconformed to.

1 The inner surface of slide cylinder (pipe, chute) should be smooth.

Before the concrete placement, the inner surface of slide cylinder (pipe, chute)

is lubricated with mortar, when water is used for lubrication, the water shall

be diverted out of the concrete placement surface and drainage measures

shall be taken on the concrete placement surface.

30

2 The use of slide cylinder (pipe, chute) should be approved by lest to

determine its height and suitable concrete slump.

3 The slide cylinder (pipe, chute) should be smooth. The parts should be

jointed firmly with protective measures to prevent any drop-off.

4 In the process of transporting and discharging the concrete mixtures,

segregation of the concrete mixture shall be avoided. It is prohibited to add water

into the slide cylinder (pipe, chute).

5 After the transportation or treating with the clogging of slide cylinder

(pipe, chute), washing shall be made promptly and washing water shall not be

allowed to flow onto the newly placed concretesurface.

7.3 Placement

7.3.1 Any preparation work for the concrete placement surface dial]

not be started until the structure foundation is approved.

7.3.2 Any loose stone, waste and mud on the rock foundation surface

shall be cleaned off. The foundation surface shall be washed and cleaned and

the washing water shall be drained away. When there s pressure ground water, it

is necessary to conduct reliable treatment.The cleaned foundation surface shall

be maintained clean and wet before concrete placement.

7.3.3 When the dam foundation is composed of soft rock or rock liable to

weathering, the following treatment measures shall be applied:

1 When preparing concrete placement surface on the soft foundation,

disturbance or remolding of the original soil shall be avoided. If the soil is remolded, it

shall be treated duly.

2 For the non-adhesive soil foundation, when the soil humidity is not enough,

the soil shall be soaked at least in depth of 15cm and its humidity level shall be kept

corresponding to the soil optimum strength.

3 If the foundation is composed of collapsible loess, special treating measures

shall be carried out.

4 The foundation surface shall be protected appropriately before the concrete

31

placement.

7.3.4 Before the concrete placement, preparation work shall be checked in detail,

including foundation treatment (or joint surface treatment), preparation for concrete

placement, formwork, steel bars and pre-embedding parts. It shall be ensure that they

are in good accordance with the design requirements and check records shall be made in

detail.

7.3.5 Before placement of the first course of concrete on the foundation surface

and the concrete construction joint surface, a layer of cement mortar, small-graded

concrete or rich mortar concrete of same strength may be placed in order to guarantee

the new concrete well bond with the foundation rock or the concrete construction joint

surface.

7.3.6 For concrete placement, the horizontal spreading method or stepped

spreading method may be used. The concrete placement shall be conducted

with certain thickness, sequence, direction, and by layers, and with the

placement surface kept smooth. For the stepped spreading method, the step width

shall not be less than 2m. When concrete placement is carried out close and near

the penstocks, shafts, tunnels and galleries, the placement shall rise in a

symmetrical and even way.

7.3.7 The layer thickness of concrete placement shall be determined

according to mixing capacity, transporting capacity, placement speed, air

temperature and vibrating capacity. In general, it is between 30cm and 50cm.

The allowable maximum thicknesses of concrete determined by type of vibrating

equipment may refer to Table 7.3.7. When the low plasticity concrete or

large vibrating machines with strong vibrating force are used, the concrete

layer thickness shall be determined by test.

Table 7.3.7 Allowable maximum thickness

of concrete placement layer

Types of vibrating equipment Allowable maximum thickness ofconcrete placement layer

32

Plug type

Vibrator 1.0 time the length of vibrating tamper (head)

Electric or pneumatic vibrator 0.8 times the length of vibrating tamper (head)

Flexible shaft type vibrator 1.25 times the length of vibrating tamper (head)

Plate type

Structure without or withone course steel bar

250mm

Structure in double courses of steel bars

200mm

7.3.8 Right after the placement, the concrete mixture shall bespread and vibrated

without any piling up. When there is any pile of coarse aggregate formed on the concrete

placement surface, it shall be spread evenly to the parts with more mortar. Those coarse

aggregate piles shall never be covered with sand mortar to avoid formation of

honeycomb. When the concrete placement is carried out on an inclined surface, the

placement shall be started from low parts, the placement surface shall be kept

horizontal and the final closing surface of the placed concrete shall be made

perpendicular to the inclined surface.

7.3.9 Vibrating of placed concrete shall follow the specifications as follows:

1 After concrete placement, the concrete mixture shall be spread

(leveled) and then vibrated. It is strictly prohibited replacing mixture spreading

by vibrating. The vibrating time shall be determined by the vibrating state and

by the moment when the coarse aggregate of concrete mixture does not sink

apparently any more and starts to bleed water. Less-vibrating and over-

vibrating shall be equally avoided.

2 The vibrating capacity of the used vibrating equipment shall be matched

with the concrete placing machinery and objective conditions of the concrete

placement surface. For the large concrete placement surface with the use of the

tower belt conveyor, the vibrating machine should be used for the concrete

mixture vibrating. In this case, the following stipulations shall be followed:

1) The vibrating rod unit shall be inserted into the concrete

mixture vertically and pulled out slowly after vibration.

33

1)The vibrating rod unit shall be moved with specified

distance and overlap.

3) When the first course of concrete is vibrated, the vibrating

rod unit shall be kept 5cm from hardened concrete surface. When vibrating the

upper concrete course, the vibrating rod head shall be inserted into lower

concrete mixture by 5cm to 10cm.

4) When conducting vibration, the distance between vibrating

rod head and the formwork shall be kept no less than half the effective radius of

the vibrating rod.

3 When hand-held vibrators are used, the following

specifications shall be followed:

1) The distance of vibrators inserted into concrete mixture shall not

exceed the effective radius of vibrators by 1.5 times and shall be determined

by testing.

1)Vibrators shall be inserted vertically into the concrete mixture in

sequence. When they are inclined slightly, the inclining direction shall be kept

identical to avoid missed vibration.

2) When conducting vibration, the vibrators shall be inserted into the

lower concrete layer by about 5cm.

3) The direct collision of the vibrator with formwork, steel bars and

embedded parts shall be strictly avoided.

5) Close attention shall be paid to the vibrating close to pre- embedded

parts, especially around water-stops and grout- stops. When necessary, manual

tamping and densification shall be applied.

6) The vibration of the first concrete layer, concrete discharging contact

zone and the concrete at the stepped slope shall be enhanced.

7.3.10 Adding water to the concrete placement surface during the concrete placement

shall be strictly prohibited. In case of the low concrete mixture workability, it is

necessary to adopt measure to enhance vibration. The bleeding water on the concrete

placement surface shall be diverted away promptly. In flow of the foreign water shall be

34

DL / T 5144 -

avoided. Drilling holes on the concrete formwork to drain water from the place

concrete is strictly forbidden because the draining water is able to carry away the

cement mortar. The cement mortar residue attached to the formwork surface, steel

bars and pre-embedded pieces shall be removed on the timely basis. Special personnel

shall be assigned to maintain the formwork to avoid its displacement and deformation.

7.3 .11 The concrete placement operation shall be continuous.

1 The allowable time interval of concrete placement shall be determined by tests.

The allowable time interval for the concrete with the common water-reducing agent can

refer to Table 7.3.11. When the allowable time interval is exceeded, the placement may be

continued provided the concrete can be remolded.

Table 7.3.11 Allowable time interval for concrete placement

AirtemperatureC

Allowable time intervalminModerate-heat Portland cement, Portland cement, common Portland cement

Low-heat Portland blast-furnace-slag cement, Portland blast-furnace-slag cement, Portland-pozzolana cement and fly

20-30 90 12010-20 135 1805-10 195 —

2 When the concrete initial setting happens partly and does not exceed the allowable

area, then the concrete placement can be continued after spreading cement mortar or

sine-graded concrete on the concrete initial setting locations.

7.3.12 The concrete placement shall be stopped when one of the 'lowing occasions

happens on the concrete placement surface:

1 The initial setting area of the placed concrete exceeds the allowed value;

2 The average temperature of the placed concrete mixture exceeds the allowable

deviation value and cannot be adjusted to the allowable range within one hour.

7.1.13 The concrete mixture on the concrete placement surface shall be removed

when one of the following occasions takes place:

1 Unqualified concrete as stipulations listed in the clause 1, 2 and 3 of the Article

7.1.9;

35

2 The low-graded concrete mixture placed into the locations of the high-graded

concrete mixture;

3 Concrete mixture can not be compacted by vibration or its wrong aggregate

gradation can make harmful effect on the structures;

4 The concrete mixture does not harden for long time and its fling time exceeds

the specified time.

7.3.14 The treatment of the concrete construction joints shall Inform to the

following specifications:

1 The concrete surface of closing placement should be flat and smooth, and

further placement surface can not be prepared until the compressive strength of the placed

concrete reaches 2.5MPa.

2 The concrete construction joint surface shall not be covered with the cement

mortar milk and shall have the coarse sand grains exposed.

3 The placement surface roughening shall be made with highpressure water jetting

machine at a pressure of 25MPa to 50MPa. Low-pressure water jetting, sand blasting,

roughening machine andartificial chiseling may be used. The start-up time for

surface roughening is determined by test. Sprinkling special roughening agent shall be

used after approval by testing.

7.3.15 The concrete of designed top surface shall be flat and smooth and its

elevation must meet the designed requirement.

7.4 Construction in rainy season

7.4.1 The following arrangements shall be carried out for construction in rainy

season:

1 The drainage facilities of the sand and gravel material storage system

should be in reliable working state;

2 The transporting vehicles and equipment shall be with measures for rain

protection and sliding prevention;

3 The concrete placement surface shall be with measures for rain protection and

waterproof-covering material;

36

4 The frequency of the aggregate water content measurements shall be increased

and the mixing water consumption shall be adjusted promptly.

7.4.2 In the day of moderate rain or above, new concrete placement surface shall not

be prevented. It is forbidden to place concrete with specified scouring resistance and

abrasion resistance and surface- finishing requirements in rainy days.

7.4.3 When placing concrete in light rain, the following measures shall be

adopted:

1 The mixing water consumption of the concrete and the concrete slump at the

mixer outlet shall be reduced adequately. When necessary, the water-binding ratio shall be

reduced adequately.

2 The water drainage from the placement surface shall be guaranteed, and water

inflow from the surrounding places into the placement surface shall not be allowed.

3 The newly placed concrete surface, especially the jointing parts shall be reliably

protected.

7.4.4 When heavy rain or rain storm starts during the concrete placement, the

concrete mixture feeding shall be stopped immediately. The placed concrete mixture shall

be vibrated to the required density and covered against the rain. After the rain, the

accumulated rain water shall be diverted away from the concrete placement surface

first, and all the parts washed by the rain water shall be treated. If the placed concrete can be

remolded, the jointing concrete mixture shall be placed and then the concrete placement can

be continued. Otherwise, the placed concrete surface shall be treated as a construction joint.

7. 4.5 Pay attention to weather broadcast. Reasonable arrangement for construction

shall be made.

7.5 Curing

7.5.1 After finishing concrete placement, water shall be sprayed on the concrete

surface in time to keep wet.

7.5.2 The requirements for concrete surface curing:

1 After finishing placement, the surface shall be kept from exposure to the

sunlight before the curing starts.

37

2 The plastic concrete shall be cured by water spraying 6h to 1 8th after the

concrete placement. The low plasticity concrete shall be cured with water mist spraying

immediately after the concrete placement and subsequent curing by watering shall be

started as early as possible.

3 The placed concrete shall be cured continuously. The concrete surface shall be kept

wet all the time in the curing period.

7.5. 3 The curing time should not be less than 28d. For the locations with special

requirements the curing time should be extended.

7.5.4 The curing shall be carried out by specially assigned personnel with detail

curing records.

38

8 Temperature Control

8.1 General

8.1.1 The concrete construction with temperature control requirement

shall conform to the specifications in this chapter. For theTemperature

control specifications related to concrete construction in lower temperature

seasons in the Chapter 9 of this standard can be referred.

8.1.2 The setting of longitudinal and transverse joints, thickness of

placement layers and time of placement intervals shall be in notedanee with

the design specifications.

8.1 3 In order to avoid concrete cracking, comprehensive measures must be adopted

in the aspects of structure design, raw material selection, mixing proportion design,

construction arrangements, construction quality, concrete temperature control, curing and

surface protection etc. Concrete placement with long period of interval for thin blocks

and early overflowing shall be avoided. The concrete placement in the contact with

foundation shall be strictly controlled. Micro expansive cement can be used after testing

and examination.

8 1.4 In order to improve cracking resistance capacity of concrete placed at

positions with cracking resistance requirements in construction, except that the

concrete strength assurance rate shall meet the requirements, concrete quality uniformity

index shall be at the quality grade "Good" and "Excellent" specified in Table 11.5.11.

8 1.5 For the concrete with the design age exceeding 28 days the cracking

resistance capacity in early stage shall be taken into consideration during its mix

proportion selection.

8.1.6 Concrete mixture temperature at the mixer outlet and temperature upturn

during concrete transportation and placement shall be controlled. The allowable placement

temperature of concrete shall meet the design specification. When the concrete

allowable temperature is not specified in design document, it can be calculated

39

according to the concrete permissible maximum temperature. The concrete placement

temperature should not be over 28°C . Adopt comprehensive measure shall be adopted to

control the maximum concrete temperature within allowable design range.

8.1 .7 In the process of construction, the placement surface of dam blocks shall rise

evenly. The height difference distance of two adjacent dam blocks shall not exceed

10m to 12m. When there is any special requirement in construction, the dam block

height difference can be increased adequately after examination and approval.

8.2 Temperature control measures

8 . 2 .1 Lowering concrete placement temperature

1 To lower the aggregate temperature in storage silos, the following measures

should be adopted:

1) The height of aggregate pile in storage silos should not b, less than

6m;

2) Taking aggregate through gallery outlets;

3) Setting shelters and spraying water mist (water mist spraying is not

suitable for sand).

2 The measures like air cooling, water soaking, cold water spraying, etc can be

used for the coarse aggregate pre-cooling. When water-cooling method is taken,

dewatering measures shall be adopter to maintain the water content in aggregate stable.

When air-cooling method is adopted, measures shall be taken to prevent aggregate

freezing (especially gravel freezing).

3 In order to prevent temperature rise, heat-insulating and heat-preserving

measures shall be adopted for moving the aggregate from the pre-cooling storage silo

to the batching plant.

4 Measures like using cold water and adding ice and other can be used to

bring down the concrete temperature during concrete mixing. When ice is added,

it is suitable to use slice ice or flake ice and to prolong the mixing time.

5 When placing concrete in high-temperature season the following measures can

40

be adopted, in accordance with the specific conditions, to reduce the temperature rise

of concrete.

1) The time of transporting concrete and waiting for unloading

shall be shortened. The concrete shall be spread and vibrated right after pouring,

timely cover the placed concrete to shorten the exposure time;

1)The equipment for transporting concrete shall be protected with measures

of heat insulation and sun shading;

2) The methods like the water mist spraying shall be adopted to lower

the temperature of the concrete placement surface;

3) The concrete shall be placed in the morning and dusk, in the night

or in cloudy days;

1) When the size of placement blocks is big, the stepped placement

method can be used, with the thickness of the placement layers less than 1.5m;

4) The concrete surface shall be covered with heat-insulating material

immediately after spreading and vibrating is finished.

6 The concrete at the foundation contact shall be placed in the favorable season.

When it has to be placed in the high-temperature season, the placement must be

conducted after examination and approved with effective measures of temperature

control..

8.2.2 Lowering the concrete temperature rise caused by the cement hydration

1 Starting from the premise that all design indexes of the concrete are accorded

with, the cement varieties with low hydration heat shall be used, and the unit cement

consumption of the concrete shall be reduced on the basis of the optimized design of

concrete mix proportions and adoption of the relevant comprehensive measures.

2 The placement layer thickness of the concrete poured at restrained position of

foundation and the old concrete shall be 1m to 2m. Time interval between the upper and

the lower layers shall be five to ten days. When cooling water pipe is embedded in

the placement layer, the layer thickness can be 3m and the interval time between layers

can be prolonged appropriately. In high-temperature season, the surface water flow can be

used to cure concrete, which is beneficial to the surface heat radiating.

41

3 When the cooling water pipe system used for initial cooling, the water-running

time shall be defined by calculation, about fifteen to twenty days in general. The

temperature difference between concrete and water shall not exceed 25r , and the speed

of water flow in pipes shall be about 0.6m/s. The direction of water flow shall be

changed once per 24h. The temperature decline per day shall not be over 1°C.

8.2.3 Diminishing the temperature difference inside and outside of the dam

In order to lower the temperature difference inside and outside of the dam so as

to prevent or reduce the cracks on the concrete surface, the temperature of dam body

shall be declined to the required design temperature before the low temperature season.

When the water cooling of the dam body in the middle period is adopted, the time of

water cooling shall be defined by calculation, about two months in general. The

temperature difference between the cool water and the internal concrete shall not exceed

20°C. The temperature and decline per day shall not exceed 1°C.

8.2.4 Surface protection

1 In low-temperature and temperature-dropping season, fresh surface protection shall

be done for the placed concrete.

2 In the season with significant temperature changes, the long time exposed

foundation concrete and important parts must be protected. For protection of the old

concrete in cold areas, its surface protective measures and protection time can be

determined according to the actual conditions.

3 The formwork removal shall be determined according to the concrete strength and

the temperature difference inside and outside concrete, avoiding removal during night or

sudden temperature drop. In very cold season, the formwork removal time shall be

postponed when the sudden temperature drop is foreseen after the formwork removal. If

the formwork must be removed, the protective measures shall be adopted.

4 The side protection of the placed concrete shall be combined with consideration of

the formwork types and material properties. When necessary, heat insulating material

lined to the internal side of the formwork or the concrete prefabricated formwork shall be

used.

42

5 The protective material and its thickness of concrete surface protection shall be

selected and defined by calculation and testing in accordance with the concrete positions,

internal and external temperature and climate conditions.

6 For placed slab structures such as backplane, apron and pier, the top (side) surface

shall be protected before water flow. The season with frequent temperature drop and low

temperature coming for the hollow space of slotted gravity dam, buttress dam and hollow

dam, it is favorable to close the hollow space and to conduct surface protection.

The inlet and outlet of tunnels, shafts, surge tanks, galleries, draft tubes, discharging

openings and other opening shall be closed before the low-temperature season. The edge

angles and projecting portions of placed concrete shall be with more protection.

7 The concrete with age below 28d shall be protected against the sudden drop of

temperature. The top surface protection shall last till the end of sudden drop of

temperature or the start of placement or upper concrete layer,.

8.2.5 Measures of temperature control for specific part

1 For the concrete used for back-filling of ponds and trenches with depth in the

bedrock over 3m, measures of temperature control like placement by layers or water

cooling and others shall be adopted to control the maximum temperature of concrete.

When the temperature of the back-filling concrete is lowered down to the designed

temperature, the placement of the upper concrete can be continued.

2 The back-filling of pre-arranged trenches can be conducted only after the

temperature of the old concrete on both sides of the trenches meets the design

requirement. Concrete back-filling shall be conducted in favorable season or low-

temperature concrete construction method shall be used .

3 The temperature of lower layer concrete shall reach the designed

requirement before the placement of the conjunction block, in addition to

control placement temperature, the construction method with in thin layers

short placement interval, and even rising shall be used, and the placement

shall be conducted in favorable season. When necessary, the measures

like the water cooling at beginning or other measures may be adopted.

43

4 When the natural cooling can not meet the temperature requirement

of the joint dam grouting, water cooling pipe system shall be embedded

during the placement.

5 The concrete placement for blocking and sealing of holes and

opening shall be conducted with comprehensive temperature control

measures to meet the designed requirements.

8.3 Temperature measurement

8.3.1 In the process of concrete construction, the measurement of the

temperature of concrete raw materials, concrete temperature at the mixer

outlet, the temperature of cooling water of the dam body and the air

temperature shall be conducted at least once per 4h with detailed records.

8.3.2 For the temperature measurement during the concrete placement, one

measuring point at least per 100m2 of concrete placement area and no less

than three measuring points for each placement layer shall be arranged. The

measuring points shall be evenly distributed on the placement surface.

8.3.3 For the temperature observation of the internal concrete of the placement

block, aside from the design requirements, measuring instruments can be embedded to

make observations according to the temperature-control requirements.

44

9 Construction in Low-Temperature Seasons

9.1 General

9.1.1 When the daily average temperature remains below 5°C

continuously for five days, or the minimum temperature remains below —3°C

continuously for five days, the concrete placement shall be conducted as the

concrete construction in low-temperature season.

9.1.2 For the concrete construction in low-temperature season, the special

construction organization design shall be prepared and the technical measures shall

be taken to ensure the concrete placement to meet the designed requirements.

9.1.3 The allowable concrete frozen critical strength in the early stage of

placement shall meet the following requirements:

1 For the mass concrete, it shall not be less than 7.0MPa (or the concrete

maturity degree not less than 1800°C • h).

2 For the non-mass concrete and reinforced concrete, it shall not be lower

than 85% of the designed strength.

9.1.4 In low-temperature season, especially for extremely cold area and

cold area, the construction positions shall not be scattered. The placed concrete

with heat-insulating requirements shall be protected with the heat-preserving measure

before the low-temperate season coming.

9.1.5 In low-temperature season, good preparation shall be made for

heating, heat preservation and anti-freezing material stockpiling (including the early

strength agent and anti-freezing additive) before placing. Relevant fire precaution

measures shall also be taken.

9.2 Construction preparation

9.2.1 The temperature regime of the storage, heating and transmission

of raw material, concrete mixing and transportation as well as the concrete

placement surface shall be calculated with the heat engineering

45

methods and with consideration of the climate conditions. Based on the

calculation results, the relevant heat-preservation measures shall be

selected.

9.2.2 The aggregate screening and washing shall be finished

before low-temperature season coming. Ready-used aggregates shall have

adequate storage and pile height, with relevant protection measures

adopted against ice, snow and freezing.

9.2.3 In low-temperature season, water should be heated before

mixing. When the average air temperature remains below —5 , the concrete

aggregate should be heated by the steam pipe batteries. The coarse aggregate

can be directly heated by steam, but this heating measure shall not affect

the water-cement ratio.

When it is unnecessary to heat the concrete aggregate, the aggregate

shall be kept from being frozen and mixed with ice.

9.2.4 Before mixing concrete, the concrete mixer shall be washed

with hot water or cleaned with steam and the collected water in the mixer

shall be emptied out.

9.2.5 Before the concrete placement on the foundation surface or

the old concrete surface, the surface temperature shall be measured. If it is

below 0°C, the placement surface shall be heated over 0°C. The heating

depth shall not less than 10cm or the surface temperature at edges and

corners of the concrete placement surface (the coldest place) shall be

above 0°C.

9.2.6 It is proper to clean the concrete placement surface with thehot air

blowers or mechanic method, but not with the high pressure hydraulic or air–water

squirt gun.

9.2 .7 When the first concrete layer is placed on the soft foundation, the

foundation soil shall not be frozen.

46

9.3 Construction method and heat-preservation measures

9.3.1 The concrete construction method in low-temperature season shall be in

accordance with the following requirements:

1 In the moderate areas the heat-preservation methods should be used and in the

areas with sand storm, the wind protection measures should be adopted.

2 In extremely cold area and cold area, it is proper to adopt the heat-preservation

method when the expected daily average temperature is over –10°C, and to adopt the

comprehensive heat-preservation method or "the warm house method" when the

expected daily average temperature is from –15°C to –10°C. For the concrete

placement surface with sand storm and not suitable to be covered with warm house, it

is proper to set the heat supply equipment under the insulating quilt. For the extremely

cold area where the average temperature difference between hottest and coldest months

is more than 42°C, careful study and preparation of the detailed construction program shall

be conducted for the construction in low-temperature season.

3 Except for the particular construction requirement, it is not suitable for construction

when the daily average temperature is below –20°C .

9.3 .2 The concrete placement temperature shall meet the design requirements. In

the moderate area this temperature shall not be below 3°C, in the cold and extremely

cold areas, this temperature shall not be below 5°C when the heat-

preservation method is used, and 3°C when the warm house method is

used.

9.3.3 When the steam heating or electric heating method is used for the concrete

construction, Specific design shall be conducted.

9.3.4 When the hear-preservation method is used for the concrete construction in

the moderate area and cold area, the following stipulations shall be followed:

1 The heat-insulating formwork shall be very reliable and the insulating layer shall

be over lapped and jointed strictly, especially on the holes and joints, to ensure the

construction quality.

2 Wind-stopping and heat-insulating facilities shall be added at the part with holes

47

and windward face.

3 The placement surface shall be covered with the heat-preserving material right after

the placement.

4 The heat-preserving material which is liable to absorb moisture shall be used.

9.3.5 The external heat-insulating curtain must be firmly fixed onto the

formwork. The internal heat-insulating material shall be smooth and reliably fixed to the

concrete surface after the formwork removal.

9.3.6 The concrete mixing time shall be extended adequately ompared with that in

normal temperature season. The specific time duration shall be determined by testing.

For the heated aggregate and concrete, it is necessary to try to shorten the transportation

length and reduce the transition cycles.

9.3.7 In the process of construction, the concrete mixture temperature at the mixer

outlet shall be carefully controlled and duly adjusted. This temperature shall be kept

without fluctuations as much as possible and the concrete placement temperature shall

be maintained uniform. The control method used shall be based firstly on heating the

mixing water. When this measure is not enough to meet the temperature requirement,

then the aggregate heating shall be used. However, the direct heating of cement shall be

not allowed.

9.3.8 If the temperature of heated water for mixing exceeds 60°C, raw material

feeding sequence shall be changed, that is the aggregate and water shall be mixed first

and then the cement shall be added to avoid the pseudo setting.

9.3.9 After placing, the exposed surface shall be insulated promptly. The insulation at

joints and edges of new and old concrete shall be enhanced. The thickness of the

insulating layer shall be doubled and the overlapping length shall not be less than 30cm.

9.3.1 0 For the concrete placement in the low-temperature season, the removal of the

formwork shall be submitted to the following specifications:

1 When removing non-bearing formwork, the concrete strength must exceed

the allowable critical frozen strength or the corresponding maturity degree.

2 The bearing formwork removal shall be determined by calculations.

48

3 The time of formwork removal and the protection after formwork removal shall

meet the requirements of the concrete temperature control and the concrete

cracking control. The internal and external temperature difference of the placed

concrete shall not exceed 20°C or the temperature drop of the concrete surface

shall not exceed 6°C in two to three days.

9.3.1 1 For the concrete quality examination, aside from testing the specified concrete

specimens, the non-destructive strength evaluation means or the concrete maturity degree

method can be used to evaluatethe early strength of the concrete (The application of the

maturity degree method to calculate the early strength of the concrete is given in the

Appendix C).

9.4 Temperature observation

9.4.1 The specifications for the temperature observation during the concrete

construction are as follows:

1 Automatic thermometric instruments should be used to observe the air

temperature outside. When the temperature measurements are conducted

manually, four measurements per day are required.

2 The temperature in the warm house shall be measured once every

four hours at the height of 50cm from the concrete surface. The air

temperature is defined by the average value of the measurements conducted at

the four corners and the center of the shed.

3 The temperatures of water, additive and aggregate are measured

once an hour. When measuring the temperature of water, additive solution

and sand, the inserting depth of temperature transmitter and thermometer

shall be no less than 10cm and for the measurements conducted in the coarse

aggregate the inserting depth shall be no less than 10cm and also 1.5 times of

the aggregate particle diameter, with the space around the measuring device

filled up by small particles. When the touch type thermometer is used,

the aggregate particle for measurement shall be taken from the depth no

less than 15cm.

49

4 The temperature of the concrete mixture at the mixer outlet, the heat

loss of the concrete mixture during transportation and the concrete placement

temperature shall be measured according to the actual need or once every two

hours. The inserting depth of temperature transmitter and thermometer shall be

not less than 10cm.

5 The internal temperature of the placed concrete block can be measured by the

devices like the electric resistance thermometer, the thermoelectric couple or the

temperature measurement hole with a depth more than 15cm and filled up by a liquid medium.

The temperature transmitter or the glass-stem thermometer can be installed in the hole for

temperature measurements.

9.4 .2 The temperature changes shall be measured more frequently within three days

of the mass concrete placement. The maximum and minimum temperature of the external

concrete shall be measure once per day. The maximum and minimum temperature of the

internal concrete shall be measured once every eight hours. Afterwards, the measurement

shall be conducted once every twelve hours.

9.4.3 During the period of sudden temperature drop and cold wave, the frequency of

temperature measurements shall be increased.

50

10 construction of embedded piece

10.1 General

10.1 .1 The type, position and size of embedded pieces of the hydraulic concrete

and the kinds, specifications and property indexes of all the materials used for their

production must be in accordance with design requirements and relevant standards.

10.1.2 All the materials used for embedded parts shall be provided with the

properties inspection report and delivered certificate by manufacturer. Before they are

embedded, all embed parts shall be checked or sampled for checking. The use of

unqualified parts is strictly forbidden.

10.1.3 The materials and components of embedded parts shall not be stored in the

open air. They shall be protected from sunlight and moisture. All kinds of internal

observation devices shall be provided with storage house and special care.

10.1.4 In construction process, the protection of the embedded parts shall be

enhanced to prevent them from damages, displacements and deformation.

10.2 Water-stop, expansion joint and drainage

10.2.1 The connection and installation of water-stop (strip)

1 The copper water-stops shall be neat and smooth. The skim, tarnishing rust and oil

stain on their surface shall be eliminated. All sand pits, nail holes and cracks shall be

treated by welding.

2 Field extension of copper water-stop should be conducted with the overlap

welding. The over lapping length shall not be less than 2cm and it shall be double-

sides welded (including the part of "nose"). The butt welding can be also used when

it is proved by tests that the connection quality can be ensured. The manual

electrode welding is forbidden in these two cases.

3 The surface of welded connections shall be smooth, without sand holes and fine

fissures nor water seepage. The connections welded in factory shall be check by

random sampling, with the sampling amount not less than 20% of the total number of

51

connections. For the connections welded in the field, their exterior appearance and

impermeability shall be checked one by one.

4 The copper water-stop shall be installed accurately, firmly, and the inaccuracy of

the central line of the nose and the central line of joint is ± 5mm. After installation to the

position, the hollow space of nose shall be filled up with plastic material.

5 All the polyvinyl chloride (PVC) water-stops and rubber water-stops that are

deformed, fissured or torn shall not be used.

6 Heat vulcanization should be used to connect rubber water-stops. The PVC

water-stop connection shall be conducted according to the requirements of the

manufacturer and heat bonding is allowed with the over lapping length no less than

10cm. All connections shall be checked one by one to ensure that they have no bubbles,

entrapped slag and false welding.

7 When necessary, the strength check shall be conducted for the connections of the

water-stops (strips). Their tensile strength shall not be less than 75 % of the original

material strength.

8 The connections of copper water-stops and PVC water-stops can be bolted type,

commonly referred to as the red copper enclosed by plastics. The bolted length shall not

be less than 35cm.

9 The water-stop installation shall be clamped and fixed and firmly

supported by formworks.

10 No horizontal construction joints shall be arranged with the range of the

water-stop sheet (strip) by 50cm upward and downward. When this is cannot be

avoided, relevant measures shall be adopted.

10.2.2 Construction of water-stopping base socket

1 For the installation of the water-stopping base socket, a trench

with the designed dimensions shall be excavated, the loose rock and

debris shall be removed and the trench surface shall be washed clean. The

concrete around the base socket shall be vibrating compacted. When its

compressive strength reaches lOMPa, the upper concrete can be placed. When

52

the compressive strength of the upper concrete reaches 2.5MPa, the

preparation for the next work sequence can be started.

2 The water-stopping trenches and sills at dam foundation shall be

checked and accepted in accordance with the dam foundation surface

requirements. The concrete surface shall be coated with the isolation agent,

but other parts shall not be polluted.

10.2.3 Preparation and installation of asphalt water-stopping well

1 The mixing proportion of asphalt mixture and asphalt

abbreviated as the filling material for the asphalt water-stopping well (asphalt

well in short) shall be determined by test according to the design

requirement. The filling materials and the mix proportion shall be uniform

in the same asphalt well.

2 The prefabricated water-stopping asphalt (filling) pillar can be

adopted.

3 When the preformed asphalt wells are used, attention shall be paid

to the following points:

1) The internal and external walls of the prefabricated

concrete wells shall be rough and shall remain dry and clean. All the

joints shall be sealed with mortar.

2) The electrical heating elements (or steam pipes) shall be firmly

embedded in accurate position. The filling material shall be grouted

section by section.

4 When the installation of the whole asphalt well is completed, the asphalt

filling material shall be heated and melted once by electric heating (or steam heating).

Then the left-over space near the well mouth shall be filled up with the filling

material, the well mouth shall be covered with the well cap and detailed records with

all data shall be made.

10.2.4 Construction of filling material for expansion joints

1 The joint surface of the expansion joints shall be neat and clean. All

53

honeycombs shall be filled up and all protruding iron piece shall be cut off.

2 The material and thickness of filling material for joint surface shall

conform to the designed requirements.

3 The joint surface shall be dry. The adhesive bitumen primer shall be applied

(brushed) first and then the veneering material shall be stuck in the preset order. Its

height shall not be lower than that of the concrete placement closing layer.

4 The veneering material shall be stuck firmly and those with damages shall be

repaired promptly.

10.2.5 Construction of drainage facilities

1 The installation of drain holes in the dam foundation shall be conducted after

completion of the curtain grouting in case when the drainage holes are located within a

distance of 30m from the curtain. The drilling of drain holes shall be carried out with

the uniform numbering (coding) according to the design drawing and

relevantdocuments and detailed original records shall be made.

2 The permissible inaccuracy of drain holes drilled in the bed rock shall be

controlled according to designed requirements. When it is not specified in design, the

drilling inaccuracy shall be conformed to the values listed in Table 10.2.5.

Table 10.2.5 Allowable error of drain holes in bed rock

Item Hole positionHole inclination

Hole depthHole depth>8m

Hole depth<8m

Allowableerror

10cm 1% 2 % +0.5

3 After drilling of the water drainage holes in the dam foundation, they

shall be washed with water until the out water is clean and then the washing

continued for another 10min. The orifice shall be protected to avoid the inflaw of dirty

water and pollutant.

4 The orifice device of drainage holes shall be processed, fixed and conducted

with rust prevention treatment according to design requirements. The connection parts

of the orifice device shall be installed firmly without water seepage and water

leakage.

54

5 The connecting section of the horizontal pipes (tubes) and conjunctions of the

drainage galleries installed in the bed rock shall all have tight contacts with the bed

rock. Before connecting, the inside of the pipe (tube) shall be cleaned to ensure free

water flow.

6 The drainage holes inside the dam body can be formed with the pipe-drawing

procedure. The pipe drawing-out time is determined by tests. Their plane position

shall conform to the design specifications.

7 When the precast no-fines concrete pipes are used for thedrain holes

in the dam body, their design strength shall be reached. All the joints shall be

sealed properly with specific person for maintenance during construction.

10.3 Cooling and joint grouting pipeline

10.3.1 The embedded pipe shall be without blockage. The oxide coating and oil

stains on pipe surface shall be wiped out.

10.3.2 The pipe connection shall be firmly jointed with thread without water

leakage and air leakage. The pipes and boxes in different shapes can be jointed by

binding. The cement mortar shall not be leaked into inside.

10.3.3 The pipe installation shall be firm and reliable. The pipes sections

through expansion joints shall be equipped with expansion ring or treated with joint

crossing measures.

1 0.3 .4 All the outlet of embedded pipe shall be protected reliably. At locations

where many outlets of the embedded pipes are concentrated, recognition marks shall

be attached. The outlet sections shall be protruding outside of the formwork by 30cm

to 50cm.

10.3.5 After installation, all pipes shall be checked with pressure water or

pressure air whether they are free for water flour. When pipe blocking or water leakage

is discovered, those trouble sections shall be treated promptly so that all pipes can be

functional.

10.3.6 In the process of concrete placement, all pipes shall be cared by

specific personnel to avoid any deformation or blockage. After the pipe is embedded

55

into concrete by 30cm to 50cm, they shall be checked with pressure water or air. All

discovered problems shall be treated promptly.

10.3.7 Detailed records and drawings shall be made for all embedded pipelines

to show their position, elevation, inlets and outlets.

10.4 Iron pieces

10.4.1 All kinds of embedded iron pieces shall be processed according to

the drawings and stored in categories.

10.4.2 Before embedding the built-in iron pieces, all oxide rust and oil stains

on their surface shall be cleaned off.

1 0.4 .3 The specifications, quantity, elevations, locations, embedded depth and

exposed length of all kinds of embedded iron pieces shall conform to the designed

requirements. They shall be installed firmly and reliably, with the accuracy meeting the

requirements of relevant regulations and standards.

10.4.4 In the process of concrete placement, all the embedded iron pieces shall

not be displaced or loosened. The surrounding concrete shall be vibrating compacted.

1 0.4 .5 For installation of bolts or iron pieces with requirement of high

accuracy, the standard boards can be adopted for fixing or the second-phase concrete

construction method can be adopted to ensure the installation accuracy.

1 0.4.6 The anchor rods installed in the bed rock or concrete shall conform to the

following specifications:

1 The allowable error of the drilling hole position: for the anchor bar of

column, it shall not exceed 2cm and for the anchor bar of reinforcement mesh, it shall

not exceed 5cm.

2 The hole diameter at the bottom shall be equal to do+20mm (do is the diameter

of anchor bar).

3 The depth of drilling hole in rock shall not be less than the design depth.

4 The deviation of inclination of drilling hole to the designed axis shall not

exceed 5% in the range of depth of the whole hole.

5 The embedded anchor bar shall not be shakable. The next construction

56

procedure can be started after that its strength of the cement mortar in the hole reaches

2.5MPa.

10.4.7 The bearing capacity of the hooks or iron rings for crane shall be defined by

calculation. When necessary, loading test shall be conducted. Their material quality shall

meet the design requirements or the Grade I steel without cold treatment shall be used. In

the process of concrete placement, the embedded hooks and iron rings shall be cared by

special personnel to avoid displacement or deformation. The embedded pieces cannot be

put into use until the concrete reaches the design strength.

10.4.8 For all kinds embedded iron pieces of access stairs, handrails and

parapets, the embedded depth shall conform to the design requirements. It can not be

used without safety inspection.

10.5 Interior observation devices

10.5.1 The installation of all kinds of monitoring instruments shall strictly conform

to the design drawings and SDJ 336 specifications and the manufacturer directions.

When any change has to be made, it must be approved by relevant authority.

1 0.5.2 All monitoring instruments shall be recalibrated or checked in accordance

with the SDJ 336 specifications. Those instruments can be embedded only in case when

they are able to meet the specified requirements.

10.5.3 The extension of instrument cable shall be conducted with the specified

cable and the vulcanizing jointer by vulcanization. The cable joint shall be insulating,

airproof and waterproof.

10.5.4 The instruments shall be numbered on electric cables according to the

drawing, with at least three places numbered for each

instrument the cable shall be additionally marked with the given number for every

20m for the whole length of the cable. Before embedding, the numbers shall be examined

one by one to ensure their correctness.

10.5.5 Before embedding the instruments, the quantity, specifications and size of all

instruments and their auxiliary parts shall be checked to ensure whether they are in

complied with the design requirements. The needed tools and materials must be made

57

available to meet the requirements of the embedment and installation.

10.5.6 During the installation, embedded instruments shall be handled with care.

When installing the instruments, the accuracy of their location, direction and angle

shall be ensured. After the instruments are fixed and located, their fixation and location

shall be checked and verified before embedding them into concrete. The aggregate

particles with diameter over 4cm in the surrounding concrete shall be eliminated and

then the surrounding concrete shall be vibrated and compacted.

10 .5 .7 The cable installation direction of a given instrument shall be laid out

along straight lines either parallel to the dam axis or perpendicular to it in the place. The

embedded cables shall be alwa.' ys kept at least 15cm away from the surface of construction

joints. The embedment of instrument cables along the dam upstream face shall be

scattered. On the cable joint-crossing sections and at the cable entries into the

observation stations, special treatment for joint-crossing, cable shearing protection

and cable impermeability improvement shall be completed.

10.5.8 During the embedment of instruments and cables, they shall be attended

by special assigned personnel. After they are embedded, the datas of instrument

numeration, coordinates and direction, embedding date, observation readings before

and after embedment and environment status shall be recorded and provided. As-built

drawings shall be prepared on the duly basis.

11 Quality Control and Check

11.1 General

11.1.1 The quality of concrete raw materials admix proportions, and the

concrete quality at main construction procedures and after setting shall be

controlled and checked.

11.1.2 In the process of concrete construction, the quality control shall be

conducted, for obtain the dynamic quality information and quality control graphics

shall be used to make the concrete quality statistic analysis, so as to take the

measures to improve and promote the concrete quality timely.

58

11.1.3 The quality control and quality assurance system shall be established.

Relevant technical personnel shall be assigned and the required checking and testing

equipment shall be provided to establish the necessary regulations of operational

technical management and quality control in accordance with the project scale and

the actual demands of the concrete quality control and management.

11.2 Quality control of raw materials

11.2.1 The raw materials of concrete shall not be used until they are

qualified after inspection.

11.2.2 In the process of concrete production, when necessary, concrete

specimen shall be sampled on cement strength, setting time and the main properties

of mixtures in mixing plant.

11.2.3 When the water source is changed or the water quality becomes

suspicious, the water for concrete mixing and curing shallalways be checked.

1 1.2 .4 The concentration of additive solution shall be checked one or two times a

day. If necessary, the fluidity of pure cement mortar (or sand-cement mortar) may be used to

check the water reduction rate of the water-reducing agent solution or the surface

tension of the air-entraining agent solution.

11.2.5 Inspection of aggregate quality

1 Quality inspection of ready-made aggregate:

1) The quality of ready-made aggregate shall be checked once every

eight hours. The inspecting items as following: for fine aggregate, that include

the fineness modulus, stone powder content (for artificial sand), mud content

and mud clod content and for coarse aggregate, that include the oversize

particle content, undersize particle content, mud content and mud clod content for

the coarse aggregate.

2) Quality inspection of the ready-made aggregate at the delivery: per

600t to 1200t of fine aggregate of the same source regard as one batch for

which the fineness modulus, stone powder content (for artificial sand only),

59

mud content, mud clod content and water content shall be checked. For coarse

aggregate from the same source and with the same size, per 2000t of crushed

stone and 1000t of gravel regard as one batch for which the oversize

particle content, undersize particle content, gill (needle-flake shaped)

particle content, mud content, mud clod content and saving of the medium

diameter sieve for D20 grade shall be checked.

3) Each batch of products ex-worked shall be attached with the quality

inspection report, including the source location, categories, size, quantity,

inspection date, inspection items, inspection result and conclusion.

4) The users shall inspect samples one or two times a month, according to the

index in Table 5.2.7, Table 5.2.8-1 and Table 5.2.8-2. When necessary, the

alkali activity tests shall be carried out regularly.

2 Sampling inspection at the mixing plant:

1)The water content in sand and small pebble shall be checked once

every four hours. More inspection tests shall be made on occasions times like

those after rain and snow.

1) The fineness modulus of sand, the stone powder content of

artificial sand and mud content of natural sand shall be checked once a day.

When the fineness modulus of sand exceeds the controlled median value by

± 0.2, the sand ratio of the mixing list shall be adjusted.

2) The over size and under size particle content and mud content for

coarse aggregate shall be checked once every eight hours.

2) The samples shall be taken and tested once per month from sand and

coarse aggregate at the mixing plant according to the items listed in Table

5.2.7, Table 5.2.8-1 and Table 5.2.8-2.

11.3 Control of concrete mixing and concrete mixture quality

11.3.1 The mix proportions of concrete can not be used until they pass the

tests, meet the designed specification and procedure requirements and pass the

examination and approval. The mix proportion list of concrete must be issued after

60

reviewed and approval. The raw ingredient materials shall be fed strictly in accordance

with the issued mix proportion list, and it is prohibited to make any arbitrary changes.

11.3.2 The measuring devices of concrete mixing plant shall be checked and

calibrated regularly (at least once a month). When necessary, random inspection

shall be conducted at any time. Before each weighing, zero point correction on the

weighing instruments shall be conducted.

11.3 .3 In concrete mixing, the uniformity, mixing time and the accuracy of

weighing devices shall be checked regularly. When problems are discovered, dealt

with it immediately.

11.3 .4 In concrete mixing, weighing of each raw material shall be checked and the

checking results shall be recorded, at least twice every eight hours.

11.3.5 The permissible deviation of raw material weight shall be controlled

according to Table 7.1.3.

11.3 .6 The concrete mixing time shall be checked once every four hours.

11.3.7 The concrete mixture shall be evenly mixed. The inspection of concrete

mixture shall be conducted according to the specifications of GB/T 9142 and SD 105-

1982.

11.3.8 The concrete slump shall be checked one or two times per every four hours.

The permissible deviation of slump shall meet the specification in Table 11.3.8.

11.3.9 The air content of the air-entrained concrete shall be checked once

every four hours. The range of permissible deviation of air content is ± 1.0 %.

Table 11.3.8 permissible deviations of concrete slump

Concrete slumpcm

Permissibledeviationcm

Concreteslumpcm

Permissibledeviationcm

Concreteslumpcm

Permissibledeviationcm≤4 ±1 4~10 ±2 >10 ±3

11.3.1 0 The temperature of concrete mixture, air temperature and temperature of raw

materials shall be checked once every four hours. 1 1.3.1 1 When necessary, the water-

binding ratio (water-cement ratio) of concrete mixture shall be checked according

to the specifications of GBJ 80 and the SD 105-1982.

61

11.4 Check and control of placement quality

11 .4 .1 Inspection of preparation before concrete placement.

1 The foundation surface or surface of concrete construction joints shall be treated

according to the requirements listed in the SDJ 249.1-1988. The quality of formwork,

steel bar and pm-embedded parts shall be checked. The concrete placement can be

started only after the certificate of concrete placement is issued.

2 The installation of metal structures and mechanical-electric equipment and the

embedment of instruments and devices shall be checked in accordance with the relevant

specifications and standards before the certificate of concrete placement is issued.

11.4 .2 After the placement of concrete mixture, its uniformity and workability shall

be observed. When any abnormality is discovered, dealt with them immediately.

11.4 .3 During the concrete placement, specified persons shall be present at site to

conduct the inspections and to make detailed records for the construction process, the

construction problems and thesolutions.

11.4.4 After the removal of formwork, the exterior appearance of concrete shall be

checked. Any quality problems or incidents like concrete cracks, honeycomb pockets,

pitted surface, staggered joint and formwork deformation shall be checked and treated

immediately. When there is any doubt toward the concrete strength or internal quality,

non-destructive inspection methods (such as: rebound method, comprehensive ultrasonic-

rebound testing method and others) or core boring, water pressure tests, etc., shall be used

to make checking.

11.5 Strength testing and evaluation

11.5.1 The concrete quality inspection in the site focuses on the compressive

strength. The compressive strength of 150mm cube concrete test specimen is defined

as the standard compressive strength.

11.5.2 The concrete sampling is mainly conducted on a random basis from the

mixer outlet. Three concrete specimen of each group shall be sampled and prepared from

the concrete of the same storage hopper or the transporting wagon box. The number of

62

specimen sampling from the concrete placement site shall be 10% of those sampled

from the mixer outlet. The strength representative value shall be determined in

accordance with the following specifications:

1 The arithmetic average value of the three specimens of each group is taken as the

representative strength of the specimen group.

2 In case the difference between the median strength and the maximum strength or

between the median strength and the minimum strength exceeds 15 % of the median

strength in one specimen group, then the median strength is taken as the representative

strength of the specimen group.

3 In case both differences between the median strength and maximum

strength and the differences between the median strength and minimum

strength exceed 15% of the median strength of one specimen group, the

strength of that specimen group shall not be used as the basis of the strength

evaluation.

11.5.3 The number of specimen taken from the same grade concrete shall

conform to the following specifications:

1 Compressive strength: For mass concrete, taking one group of specimen

from every 500m3 concrete at 28d age, and one group of specimen from every

1000m3 concrete at design age; For non-mass concrete, taking one group of

specimen from every 100m3 concrete at 28d age, and one group of specimen

from every 200m concrete at design age, one group of specimens shall be

sampled and prepared.

2 Tensile strength: Taking one group of specimen from every 2000m3

concrete at 28d age and one group of specimen from every 3000m3 concrete

at design age.

3 Other main specific requirements to the concrete like anti-freezing

and anti-seepage capabilities shall be checked by sampling during

construction. The sampling number may be one or two groups from the

main locations of construction in each quarter of the year.

63

11.5.4 In order to forecast the concrete strength, fast testing or testing the

concrete strength at 7d age should be made.

11.5.5 The moulding, curing and testing of concrete specimens shall be

conducted according to the specifications of SD 105-1982. 11.5.6 For

testing and evaluation of concrete strength: The average strength and

the minimum strength value of the acceptance tested batch shall meet the

following requirements simultaneously.

(11.5.6-1)

Where: — average value of concrete strength, MPa;

fcu,k— standard value of concrete strength at the design age, MPa;

K_--acceptance evaluation coefficient, which can beselected from Table

11.5.6, in accordance with the value n of statistical group number of the acceptance

tested batch;

t_--probability coefficient, which can be selected fromTable Al of Appendix A;

σ0-- standard deviation of concrete strength of theacceptance evaluation

tested batch, MPa;

--the minimum strength value in group n, MPa.

Table 11.5.6 Table of k value of acceptance evaluation coefficient

n 2 3 4 5 6-10 11-15 16-25 >25K 0.71 0.58 0.50 0.45 0.36 0.28 0.23 0.20

Notes: 1 The concrete of the same acceptance tested batch shall be prepared with same strength standard, mix proportion and basically identical production technology. For the concrete cast-in-place, it should be accepted according to acceptance items of the construction or batches divided in month.2 For the strength of concrete of acceptance batch, when the calculated value of the standard deviation cro is less than 0.06fc., k, (ro=0.06fm, k shall be adopted.

64

11.5.7 The age of concrete sampled for testing comprehensive strength shall be

identical to the concrete design age for evaluation of concrete quality acceptance. The

process control of concreteproduction quality shall be conformed to the compressive

strength of the specimens prepared with the standard curing for 28d. The compressive

strength ratio of concrete at different ages shall be determined by testing.

11.5.8 When the testing results of the concrete compressive strength specimens can not

meet the acceptance standard requirement stipulated in Article 11.5.6 or the representation of

the concrete specimen strength appears to be not convincible, concrete core specimens can be

drilled from the concrete structure for testing or non-destructive inspection can be used in

accordance with the specifications. When the obtained result still can not meet the

requirements, the structural safety degree shall be calculated for the finished structure in

accordance with the actual conditions, and necessary remedy measures or other treatment

measures shall be taken according to the requirement .

11.5.9 The acceptance percentage of anti-freezing testing of

concrete at design age shall not be less than 80%. The anti seepage testing results of

concrete at design age shall meet the design requirements.

1 1.5.1 0 Aside from making quality evaluation for the concrete strength batch by batch

and stage by stage, the statistical analysis shall be conducted for the concrete strength of the

same strength standard and the same age in each statistical cycle. The average value of

concrete strength mfic., standard deviation a and the probability rate P shall be calculated with

statistical methods. In addition, the percentage rate Ps which not less than the standard design

strength shall be also calculated. The relevant calculation methods are given in Appendix A.

1 1 .5 .11 The concrete production quality is presented by thestandard deviation value a

of the compressive strength obtained from the specimens prepared at the construction site at

age of 28d.

Table 11.5.11 Quality standard of concrete production

Evaluation index Quality gradeExcellent Good Common Bad

65

DL / T 5144 -

Standard deviationofconcrete strengthatdifferent strength

≤C9020 <3.0 3.0-3.5 3.5-4.5 >4.5C9020—C9035 <3.5 3.5-4.0 4.0-5.0 >5.0

>C9035 <4.0 4.0-4.5 4.5-5.5 >5.5

Percentage (Ps) of not less than thestandard design strength value ≥90 ≥80 <80

11.5.12 Variation coefficient 6 1, of concrete strength of one

specimen group used to measure the testing systematic error shall not exceed 5%.

The calculating method and evaluation standard is given in the Appendix A, articles

A.0.4 and A.0.5. When the variation coefficient 61, is more than 5 %, the reasons for

that shall be found out and the relevant improvement measures shall be taken.

1 1.5.13 In concrete construction, the results of various testing items shall be

put in order and processed promptly and report them to the department in charge on a

monthly basis. When there are any serious quality problems, those shall be reported to

the authority immediately.

1 1.5.14 For the completed concrete structures, the concrete core drilling and

water pressure tests shall be made appropriately. For concrete dam, the core drilling

and water pressure tests may be conducted with 2m to 10m of core depth for every

10,000m3 ofconcrete. The core locations, testing items, water pressure testing

positions and evaluation criteria of water absorption shall be determined on the

actual conditions at worksite. For the reinforced concrete structures the inspection

shall conducted mainly with non-destructive methods, but when necessary, the core

drilling can be used for evaluating the concrete.

The drilling, processing and testing of concrete core may be conducted with

reference to the specifications of CECS 03.

66

7

Appendix A (Normative Appendix)

Calculation methods for average strength

standard deviation , strength assurance rate P and

variation coefficient in one batch

A.0.1 The average strength (mfcu) of concrete can be calculated with the following

formulas:

(A.1)

Where: --average strength of specimens in group n, MPa;

--strength of specimens in group i, MPa;

n--number of specimens group.

A.0.2 Standard deviation of concrete strength (a) and percentages no less than

standard design strength (Ps) can be calculated based on the formulas below:

1 Standard deviation (A.2)

2 Percentage (A.3)

Where: ―― strength of concrete specimens of group i instatistical

cycle, MPa;

N――number of concrete specimen group with the samestrength

standard in statistical cycle;

--average strength of concrete specimens group N in statistical cycle, MPa;

n0 ――number of concrete specimens groups with strength not less than the

67

DL / T 5144 -

standard value in statistical cycle.

The calculating formulas for standard deviation 60 of concrete strength in the

acceptance batch is the same as the formulas for a.

A.0.3 Strength assurance rate P:

1 Probability coefficient calculation

(A.4)

Where: t --probability coefficient;

--average strength, MPa;

--standard design strength, MPa;

--standard deviation of concrete strength, MPa.

2 The relationship of the assurance rate P and probability coefficient t can be

obtained from Table A.1.

Table A.1 Relationship of assurance rate and probability coefficient

A.0.4 The variation coefficient of concrete in one batch (60 can be calculated with

the following formulas:

TableA.1 relationship of assurance rate and probility coefficient

Assura-nce rate P

%

65.5

69.2

72.5

75.8

78.8

80.0

82.9

85.0

90.0

93.3

95.0

97.7

99.9

Probabi-lity

coeffici-ent

0.40

0.50

0.60

0.70

0.80

0.84

0.95

1.04

1.28

1.50

1.65

2.0 3.0

The average strength of concrete in one batch ( ) and the standard deviation ( )

may be calculated with the following formulas, by using the strength data accumulated

continuously in normal production:

68

(A.6)

(A.7)

Where: --variation coefficient of concrete strength in one batch;

--standard deviation of concrete strength in one batch, MPa;

--average strength of concrete specimens in group n, MPa;

--difference between maximum and minimum strength

of three specimens in group i, MPa;

n--specimen group, which shall not be less than 30;

-- strength value of concrete specimens in group i, MPa.

A.0.5 Test level grades assessed by variation coefficient of concrete strength in one

batch (6b) are listed in Table A.2.

Testing level Excellent Good Common Bad

Variation coefficient inbatch

In the site <4 4-5 5-6 >6

Indoors <3 3-4 4-5 >5

69

Appendix B(Informative Appendix)Calculation method of alkali content in concrete

B.0.1 Alkali content in moderate-heat cement concrete

Alkali content in concrete (kg/m3) = alkali content in moderate-heat cement

(%) consumption of cement (kg/m3) +0.2 alkali content in fly ash (%)

consumption of fly ash (kg/m3)+ alkali content in additive ( % ) consumption

of additive(kg/m3)

B.0.2 Alkali content in low-heat cement concrete

Alkali content in concrete (kg/m3) = alkali content in low-heat cement

clinker ( % ) consumption of cement clinker (kg/m3)+ 0.5 alkali content

in slag( % ) consumption of slag (kg/m3)+

0.2 alkali content in fly ash(%) consumption of fly ash + alkali content

in additive(%) consumption of additive (kg/m3)

70

Appendix C(Informative Appendix)Calculating early strength of concrete bymaturity degree method

C.0.1 Ripening degree method:

The concrete strength is function of product of its curing age and

temperature. The strength is almost same if the product of different age and

temperature is equal. The method to calculate the concrete strength with this

product is called maturity degree method.

The maturity degree method has many presentations. This standard

recommends calculating concrete strength with the equivalent age method and

the maturity degree method.

The equivalent age method is a specific application of maturing degree

method. The concrete curing temperature in low-temperature construction

seasons is variable. In the condition of same concrete raw materials,

admixture and mix proportion, the relationship between construction

curing temperature and standard curing temperature (20°C) is determined

by testing and analyses is defined as equivalent coefficient. The product of the

actual curing temperature and curing time multiplied by the equivalent

coefficient is considered as the equivalent age. The concrete strength to be

determined can be calculated on the basis of the strength data of concrete

specimens with different curing ages and standard curing condition. These

strength data are provided by the laboratory in which the strength tests are

conducted.The maturity degree of concrete is the accumulation of product

of equivalent age and standard temperature. The calculation of the concrete strength

by maturity degree method is more suitable to the concrete construction conducted with the

heat accumulation method and comprehensive heat accumulation method.

C.0.2 Applicable scope and application conditions of the maturity degree

method:

71

1 This method can be applied for concrete construction with heat accumulation

method, hothouse method or comprehensive heat accumulation method.

2 This method can be applied for the strength forecast within the range less than

60% of the standard concrete strength value.

3 When the forecast of the concrete strength is conducted with this method, it is

necessary to use the actual concrete raw materials and mix proportion adopted for the

construction to prepare no less than five groups of standard cubic specimens that are cured

under standard conditions to obtain the concrete strengths at the age of 3d, 5d, 7d, 14d and

21d.

4 When this method is used, it is necessary to obtain the concrete curing time

and temperature measurement data (temperature and time) in the field.

C.0.3 Calculation of the concrete strength with the equivalent age method should be

conducted based on the following steps:

1 By regression analysis on strength statistics of standard curing specimen at

different ages, the curvilinear equation below is formed:

(C.1)

Where: --compressive strength of concrete cube, MPa;

d--concrete curing age, d;

a, b_parameter obtained by regression analysis upon results

of strength tests of concrete specimens cured under standard

conditions.

2 In accordance with the measured temperature data of concrete curing in the

field, calculate the equivalent age (equal to standard curing time at 20°C) that the

concrete has reached is calculated by formula (C.2).

(C.2)

Where: t_equivalent age, h;

72

DL /T 5144 -

_--equivalent coefficient with the temperature at T, which

is obtained according to Table C.1;

___time duration with temperature at T, h.

Table C.1 Table of temperature T and equivalent coefficient ar

TemperatureT°C

Equivalentcoefficient

TemperatureT°C

Equivalent coefficient

TemperatureT°C

Equivalent coefficient

50 3.16 37 2.07 24 1.2249 3.07 36 1.99 23 1.1648 2.97 35 1.92 22 1.1147 2.88 34 1.85 21 1.0546 2.80 33 1.78 20 1.0045 2.71 32 1.71 19 0.9544 2.62 31 1.65 18 0.9143 2.54 30 1.58 17 0.8642 2.46 29 1.52 16 0.8141 2.38 28 1.45 15 0.7740 2.30 27 1.39 14 0.7339 2.22 26 1.33 13 0.6838 2.14 25 1.27 12 0.64

Table C.1 (continue)

TemperatureT°C

Equivalentcoefficient

TemperatureT°C

Equivalentcoefficient

TemperatureT°C

Equivalentcoefficient

11 0.61 2 0.32 -7 0.1510 0.57 1 0.30 -8 0.149 0.53 0 0.27 -9 0.138 0.50 -1 0.25 -10 0.127 0.46 -2 0.23 -11 0.116 0.43 -3 0.21 -12 0.115 0.40 -4 0.20 -13 0.104 0.37 -5 0.18 -14 0,103 0.35 -6 0.16 15 0,09

3 Equivalent age t is introduced as d into formula(C.1) to calculated the

strength.

C.0.4 For concrete construction with the heat accumulation method or the

73

comprehensive heat accumulation method, the concrete strength calculation by the

maturity degree method can be conducted with the following steps:

1 A maturity-strength curvilinear equation is formed on the basis of regression

analyses of concrete strength data at different ages which are obtained from concrete

specimens cured under standard conditions.

(C.3)

(C.4)

Where: _--concrete compressive strength, Mpa. When adoptingcomprehensive

heat accumulation method, Jc.„ shall be multiplied by adjusting coefficient 0.8;

N--concrete maturity degree, °C •h;

T --average temperature of concrete in the time interval t, ;

t --time duration with temperature at T, h.

2 The strength fcu can be calculated by introducing the concrete maturity degree N

into the formula (C.3)

74

Appendix D(Informative Appendix)Property indices of joint-sealing water-stop material

D.1 Metallic water-stop

The main properties of copper strip in different states are shown in Table D.1.

Table D.1 Properties of copper strip in different state

Type StateThicknessmm

Tensile strength MPa

Expansionrate%

Width mm

T2, T3 M(soft) 0.5 ~1.0 ≥196 ≥.32≤600TP1, TP2 Y(semihard) 0.5~1.0 245-343 ≥8

The main physical and mechanical indices of red copper sheets are shown in Table

D.2.

Table D.2 Physical and mechanical indices of red copper sheet

Items Unit Index

Tensile strength MPa ?-.240

Expansion rate % 330

Cold bendingCold bending of 180°, no cracking forcontinuous bending 50 times in the range of 0°to 60°

Relative density 8.89

Melting point V 1084 5

D.2 Rubber water-stop

The property and performance indices of rubber water-stop are shown in Table D.3.

Table D.3 Property and performance indices of the raw material and

finished product of rubber water-stop

Items UnitNatural rubber

Synthetic rubber

Finished product of rubber

Hardness (shore A) Degree 60±5 60±5 60±5

75

Expansion strength MPa ≥18 ≥16 14(Maximum elongation) % ≥450 ≥400 3450Permanent deformation by fixedelongation

% ≤20 ≤25 28±2

Tearing strength kN/m ≥35 ≥35Brittle temperature °C ≤-45 ≤ -40

Hot

air

agi

ng 70°C x72h

Hardnesschanges (shoreA)

Degree ≤+8

Change rate oftensile strength(decline)

% ≤10

Change rate oftensile stretch(decline)

% ≤20

Ozone aging at 50pphm -20%-48h

Grade 2 Grade 0

D.3 PVC water-stop

The main physical and mechanical performance of the PVC water-stop are shown

in Table D.4.

Table D.4 Physical and mechanical performance

of PVC water-stop sheet

Items UnitTestingmethod

perfor- mance index

Items UnitTesting method

perfor- mance indexTensile

strengthMPa GB1040 >14

Acc

elle

rate

d al

kali

-re

sies

tanc

e

Quality change rate

%JISK6773

±5

Elongation at breaking

%GB1040 ≥300 Strength

changerate

%JISK6773

±20

Hardness (shore)

GB2411 >65ElongationChange rate

%JISK6773

±20

Relative density

ASTM D792

1.07

Acc

elle

rate

d al

kali

-re

sies

tanc

e

Quality changerate

%JISK6773

±5

Brittletemperature ℃

ASTMD746 ≤

37.2

Strengthchangerate

%JISK6773

±10

Water Elongation JISK6773absorption

rate% GB 1034 <0.5 change

rate% ±10

ASTMVolatiliz- % D1023— <0.5

89

76

77