.-CJ?...aif'Vlk.as:JVl{Jam Limited

(/I qovt. of I tulia VrufertakjneJCorporate Office:lst Floor, '8' Block, August Kranti Shawan, Shikaji Cama Place, New Delhi-110066

Tel:+9111 26738553, Fax: +9111 26738573, Email: pksharma@rvnl.org

No. C/200S/Standard Specification/Pt. I Dated: 04.02.2015

All CPMs/GGMs/GMs,AGMs & DGMs,RVNL

Sub: RVNL's Standard Specifications for Materials and Works - A&C no. 18

Addendum/Corrigendum slip no. 18 dated 04.02.2015 to RVNL's StandardSpecifications for Materials and Works is enclosed for your information and guidance.

These changes shall be applicable to all new tenders.

This issues with the approval of Director/Projects.

(I\~A -~-e~'1~'1'1r-

(P.K. Shanna)General Manager/Project-II

Copy to:

(i) Secy to CMD - for kind information of CMD please.

(ii) OF, DO, DP - for kind information please.

(iii) ED/HQ, EDlWorks, EDllnfra, ED/P, ED/P-II, ED/Electrical, ED/S&T, EDfMech &CGM/Metro/Kolkata - for kind information please.

Page 1 of 6

ADDENDUM/CORRIGENDUM SLIP NO. 18 DATED 04.02.2015 TO RVNL'sSTANDARD SPECIFICATIONS FOR MATERIALS AND WORKS

I EngineeringI WorksI Vol 1 "7.8 Requirements for Design Mixes: Trial Mixes (ForI .,1 Chapter-3 Strengtb)

I "BfiSdgtes t (d)1 I t The Contractor is entirely responsible for the design of the

- rue ura . Th desi . h b d b hC t

" concrete mixes. e esign IS owever to e approve y t eoncre e E· A 18k before cornmenci . .ngmeer. t east wee s etore commencmg any concreting m

the works, the contractors shall make trial mixes using samples ofcoarse aggregates, sand, water, super plasticiser and cement,typical of those to be used in the works, and which have beentested in an approved laboratory. A clean dry mixer shall be usedand the first batch discarded.

S.No.

Referenceof Clause

No.1.

II

Clause-7.S I

(Page 30 & I31 of 156)

Details of Addendum/Corrigendum to Clause underreference

Replace existing clause with the following;

2. The mix shall be designed to produce the grade of concretehaving the required workability, durability and a characteristicstrength not less than appropriate value given in following Table.The procedure given in IS: I0262 may be followed for mixdesign.

TABLE: GRADES OF CONCRETE.. --.---

GRADE SPECIFIEDDESIGNA CHARACTRISTICTfON COMPRESSIVE

STRENGTHAT 28 DAYS N/mm 2

f-_ .._._ ...-. ---_.- ---- --M 20 20---_ ..- "---M 25 25M 30 30M35 35M40 40M45 45M50 50M55 55M60 60

NOTE - In the designation of concrete mix, the letter Mrefers to the mix and the number to the specifiedcharacteristic compressive strength of l50mmcube at 28 days, expressed in N/mm2

3. Suitable Water reducing admixtures or super-plasticizingadmixtures are to be used with the prior approval of the Engineerfor getting desired workability and strength of the concrete. Noextra payment shall be made for such admixtures.

Page2of6

~)~

,----.----------.,-----------------------------------------------------~s. I Reference I Details of Addendum/Corrigendum to Clause underNo. of Clause I reference

~---r----N-~----------------~---=---~.----~~-----~----------~I 4. Whenever there is a significant change in the quality of any of theI ingredients for concrete, the Engineer may at his discretion orderI the carrying out of fresh trial mixes. All costs for trial mixes andi tests shall be to the Contractor's account and held to be included

in the contract rates.

5. Before commencing the works the Contractors shall submit to theEngineer for approval full details of the preliminary trial mixesand tests.

6. When the proportions of a concrete mix have been approved bythe Engineer, the contractor shall not vary the quality or source of

! the materials or the mix without the written approval of theI Engineer."

2. : Engineeringi Works -Vol. 1 ,Chapter-3"Bridges (d)

,-- StructuralConcrete"

I New Clause- 9A underclause 9.0(Page 33 of156)

Add a new clause 9A under existing clause 9.0 as under;

"9A Ready Mixed Concrete

i) Use of Ready Mixed Concrete - Ready mixed concrete maybe used, wherever required. It shall conform to thespecifications of concrete, as laid down in this Code. For otheraspects, which are not covered III this Code, IS:4926(Specifications for Ready Mixed Concrete) may be referred to.

ii) Effect of transit (transportation) time on Ready MixedConcrete: As ready mixed concrete is available for placementafter lapse of transit time, reduction in workability occurs,which may lead to difficulty in placement of concrete. Inaddition, 10 case of longer transit time, initial setting ofconcrete may also takes place, which may render it unusable.Thus, while planning for using of Ready Mixed Concrete,these aspects should be kept in view.

II

iii) Checking suitability of Admixtures:- Generally admixtureslike water reducing agent, retarder etc. are used in ReadyMixed Concrete for retention of desired workability and toavoid setting of concrete. In such cases, admixtures should betested for their suitability as per IS:9103 at the time offinalizing the nux design. Regarding specification ofadmixtures, clause 5.0 of this section may be referred to.

I

I

iv) Re-tempering with Concrete - Under any circumstances,retempering i.e. addition of water after initial mixing shall notbe allowed, as it may affect the strength and other properties ofconcrete.

~page30f6

s. Reference I Details of Addendum/Corrigendum to Clause under

'I,NO. of ~~~se II v) referenceTime Period for delivery of concrete: The concrete shall be

I delivered completely to the site of work within 1Yz hours, (when the atmospheric temperature is above 20°C) and within I

I 2 hours (when the atmospheric temperature is at or below

II 200q of adding the mixing water to the dry mix of cement and

aggregate or adding the cement to the aggregate, whichever isI earlier. In case, location of site of construction is such that this II time period is considered inadequate, increased time period I'

may be specified provided that properties of concrete havebeen tested after lapse of the proposed delivery period at thetime of finalising mix design.

~----+---,-----,---'--'--.--------------------3. Engineering

'I Works -Vol. 1, Replace existing clause with the following;

, Chapter-3 "160 ACCEPTANCE CRITRRIA"Bridges (d) I .- Structural I J 6.1Concrete"

Clause -16.0 (Page41 to 43 of156)

vi) Transportation of Ready Mixed Concrete: The ReadyMixed Concrete shall be transported in concrete transitagitators conforming to IS: 5892 (Specification for concretetransit mixers and agitators). Agitating speed of the agitatorsduring transit shall not be less than 2 revolutions per minutenot more than 6 revolutions per minute."

Compressive strength - When both the following conditionsare met, the concrete complies with the specified compressivestrength:

a) The mean strength determined from any group of four,consecutive test results complies with the appropriatelimits in column A of table given below;

b) Any individual test result complies with the appropriatelimits in Column B of table given below. '

16.2 Flexural strength --When both the following conditions aremet, the concrete complies with the specified flexural strength;

(a) The mean strength determined from any group of fourconsecutive test results exceeds the specifiedcharacteristic strength by at least 0.3 N/mm2

.

(b) The strength determine from any test result is not lessthan the specified characteristic strength less 0.3 N/mm2

.

~ Page' of G

S. ReferenceNo. of Clause

No.

Details of Addendum/Corrigendum to Clause uilde~reference ~

TABLE - CHARACTERISTIC COMPRESSIVESTRENGTH COMPLIANCE REQUIREMENTS

(Clause 16.1 & 16.2)

16.3 Quantity of Concrete Represented by Strength Test IResults- The quantity of concrete represented by a group of 4consecutive test resuits shall include the batches from whichthe first and last samples where taken together with allintervening batches.

For the individual test result requirements given in column Bof table given above or in item (b) of clause 16.2 only theparticular batch from which the sample was taken shall be atrisk.

Where the mean rate of sampling is not specified themaximum quantity of concrete that four consecutive testresults represent shall be limited to 60 rrr'.

16.4 [f the concrete is deemed not to comply pursuant to 16.2, thestructural adequacy of the parts affected shall be investigatedand any consequential action as needed shall be taken.

16.5 Concrete of each grade shallbe assessed separately.

16.6 Concrete shall be assessed daily for compliance.

16.7 Concrete is Iiable to be rejected if it is porous or honeycombed; its placing has been interrupted without providing aproper construction joint. The reinforcement has beendisplaced beyond the tolerances specified; or constructiontolerances have not been met. However, the hardened concretemay be accepted after carrying out suitable remedial measuresto the satisfaction of the Engineer.

II

I 16.8 If the concrete produced at site does not satisfy the above

Istrength requirements, the Engineer will reserve the right to

U' .L- re_q_u_ir_e_t_h__e_c_o_l1_t'-ra_c_to_r_t_o_im_p_f-,,-o_v_e_t_h_e_m_e_th_o_d_S_o_f_b_a_t_c_h_in_g_,_th_e-->.quality of the ingredients and redesign the mix with increased

cement content, if necessary. The Contractor shall not be

Group oftest results

Specifiedgrade

A BThe mean of thegroup of test resultexceeds the speci fiedcharacteristiccornpressi ve strengthby at least:

Any individual test Iresult is not less than Ithe characteristic Icompressive strength Iless: ,

Nzrnm"Any I

I

conse;utive IM20&above 3 3

I

~ P'ge50!6

Details of Addendum/Corrigendum to Clause underireference I

entitled to claim any extra cost for the extra cement use~the modifications stipulated by the Engineer tor fulfilling the I

strength requirement specified.

16.9 It is the complete responsibility of the contractor to redesignthe concrete mixes by approved standard methods and toproduce the reinforced concrete conforming to thespecification and the strength requirements approved by theEngineer. It is expected that the contractor will havecompetent staff to carry out this work.

16.10 As frequently as the Engineer may require, testing shall becarried out in the field for:

(a) Moisture content and absorption and density of sand and Iaggregate. !

(b) Silt content of sand.

(c) Grading of sand and aggregates.

(d) Slump test of concrete.

(e) Concrete cube test.

(f) Permeability test for concrete as per DrN 1048 (Part-I).

(g) Density and pH value of Plasticizer.

The Contractor shall provide and maintain on site at all times,until the works are compieted, equipment and staff requiredfor carrying out these tests. The Contractor shall grant theEngineer or his representative full access to his laboratory atall times and shall produce on demand complete records of alltests carried out on site.

Before concreting commences on any section of the works the1 I Contractor shall obtain approval of the Engineer or his II I representative as regards the form works and reinforcements I

I I, conforming with the drawings. He shall also indicate to the I

'L I'-- ~ E__ng_i_n_e_e._r_in~W__ri_ti_n._g_a_n_d__o_b_ta_i_n_h_i_s_a_p_p_r_6_v_a_1_fo_r__p._o_S_it_io_n_s_o_f_1--.-J construction joints." .

I ;~. rI

Referenceof Clause

No.

----0----0---

Page 6 of 6