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International Journal of Civil Engineering and Technology (IJCIET)

Volume 9, Issue 7, July 2018, pp. 1000–1011, Article ID: IJCIET_09_07_105

Available online at http://www.iaeme.com/ijciet/issues.asp?JType=IJCIET&VType=9&IType=7

ISSN Print: 0976-6308 and ISSN Online: 0976-6316

© IAEME Publication Scopus Indexed

INVESTIGATION ON COST EFFECTIVE SLAB

SYSTEM HAVING DIFFERENT TYPES OF

MICRO REINFORCEMENT

Umesh S.S.

Research Scholar and Associate Professor, Department of Civil Engineering,

Mangalore Institute of Technology and Engineering, Moodbidre, Karnataka, India

Dr.A.V. Pradeepkumar

Adjunct Professor, Department of Civil Engineering,

Mangalore Institute of Technology and Engineering, Moodbidre, Karnataka, India

ABSTRACT

The conventional reinforced concrete has two basic inefficiencies. i.e. a typical

125 mm thick slab weighs 2.94 kN/m2. This is to be designed for live load 1.96 kN/m

2.

This becomes a design load of 4.90 kN/m2 and self-weight is 60 % therefore structural

efficiency of the RCC slab is only 40 %. The concrete in tension Zone hardly takes any

stresses as the concrete is week in tension and becomes expensive as concrete is not

resisting any tension load. Keeping in view the above two facts it is proposed to

investigate alternate roofing system. This research investigation focused on casting

cost effective slab system with combination of different types of Micro reinforcement

in concrete. The slab is thinner compared to conventional RC slab. This innovative

construction technique promises savings in cost, construction time, material and

labour compared to any traditional roofing system currently in use, achieving better

performance in strength, deflection and durability.

Keywords: Micro truss reinforcement, Flexure, Deflection

Cite this Article: Umesh S.S and Dr. A.V. Pradeepkumar, Investigation on Cost

Effective Slab System Having Different Types of Micro Reinforcement, International

Journal of Civil Engineering and Technology, 9(7), 2018, pp. 1000–1011.

http://www.iaeme.com/IJCIET/issues.asp?JType=IJCIET&VType=9&IType=7

1. INTRODUCTION

Food, clothing and shelter are the basic needs for every human being. Every government

worldwide trying to fulfill affordability comfort to the every citizen is the challenging goal.

The word ‘affordability’ can be defined as the ratio of the housing rent to the income of the

house hold. The ‘affordability’ can be different for different income groups such as below

poverty line [ BPL] group, economically weaker sections [ EWS], low income group[ LIG],

and middle income group [MIG].

Investigation on Cost Effective Slab System Having Different Types of Micro

Reinforcement


Due to significant urbanization, the whole world is facing housing shortage. Today,

worldwide about 320 million households in urban areas are at substandard levels. India, a

developing country, is also facing a huge housing demand for more than 6 crores housing

units. By 2022, this is expected to reach 11 crores. In order to meet the huge housing demand

in India, it is necessary to switch over mass housing and cost effective construction

technology and materials.

Cost effective construction technologies aim to cut down construction cost by using

alternatives to conventional construction practices and input. Construction cost can be

reduced through using locally available appropriate material along with improved skill and

technology without sacrificing the strength, performance and durability of the structure. It is

observed that increase of construction cost up to 15 percent every year due to the cost of basic

building materials such as steel, cement, bricks, sand and other materials as well cost of

labour. As a result, construction cost becoming beyond the affordable limit in particular for

low-income groups of the population as well as middle-income groups. Therefore it is

necessary to adopt cost-effective construction, either by up gradation of conventional

construction method using locally available materials or using modern construction materials

and techniques.

Structural floors/roofs account for the substantial cost of a building in a normal situation.

Therefore, any savings achieved in floor/roof considerably reduces the cost of the building.

Traditional cast– in-situ concrete roof involves the use of temporary shuttering which adds to

the cost of construction and time. Use of standardized and optimized roofing components

where shuttering is avoided prove to be economical, fast and better in quality. This

investigation focused on the casting of cost-effective slab system with a combination of

different types of micro reinforcement. The slab is thinner compared to the conventional slab.

This innovative construction technique promises savings in cost, construction time, materials

and labour compared to any traditional roofing system currently in use, achieving better

performance in strength, deflection and durability

2. LITERATURE REVIEW

Several attempts have been made by researchers to propose cost-effective alternatives to

conventional solid RC slabs. The underlying principle in these alternatives is that portion of

Concrete below the neutral axis (Tension Zone) is either eliminated, as in the case of voided,

ribbed, grid or waffle slabs are replaced by a relatively cheaper filler material. A brief survey

of literature about the alternatives to conventional concrete slab has presented below

Abdul Rahman [1] et.al., carried out research on the feasibility of precast prestressed

concrete slab incorporating structural hollow clay blocks in floors and roofs. In this study, the

precast slab strips have been tried out on a large scale of the roof of a school building at

Adyar in Madras. The total area of the roof was 420 m2. The slab strips were precast in the

pre-casting yard. All the precast slab strips had uniform width 0.57 m and 3.80 m spans and

thickness 0.83 m and a self-weight of 0.58 kN /m. The slab strips were prestressed in a long

line pre-tensioning bed by two 5mm diameter high tensile steel wires, one in each of the two

outer longitudinal ribs, and two 4 mm diameter high tensile wires in the middle longitudinal

rib. The total initial prestressing force imparted through the four wires was about 8.5 tones.

The concrete used in the precast slab strips had a mix proportion slightly richer than 1: 1.5:3

by weight. The maximum size of aggregate used was 10mm. The hourdi blocks used in the

work had an overall cross-section size of 230mm x 830mm with a length of 300mm. The

longest one precast slab strip weighs only 2.25kN. The stability of the precast slab strips for

large–scale application was further checked by field loading test. After testing, the actual

Umesh S.S and Dr.A.V. Pradeepkumar


ultimate load carried by the composite slab strip was 4.32 kN /m which were in addition to the

self-weight of 1.127 kN /m.Sharma [2] et.al., carried out a study on design and construction of

precast hollow or ribbed slab. In his study, he developed a simple design procedure based on

the ultimate strength design concepts of conventional solid slabs for precast hollow and

ribbed slabs has been developed. The variation of the flexural stiffness of the precast hollow

trough or cross ribbed structural forms due to the creation of voids has been derived and

expressed graphically in relation to conventional equivalent solid slab rigidity. By using,

developed formula, judicious balancing of the width of the ribs and thickness of the flanges in

relation to the spacing of ribs and effective depth respectively, considerable economy and

saving of time in construction can be achieved, aside from obtaining an attractive structure.

This design procedure is limited to short intermediate building spans. Desayi, [3] et.al.,

focused the research on, an experimental and semi–analytical study on the strength of

fibrocement roofing elements tested under symmetric two point loading are presented. Nine

trapezoidal – shaped fibrocement roofing elements were cast and tested. The variables

included were span / depth ratio, amount of longitudinal reinforcement and the type of mesh

wire. Methods of computing cracking load, ultimate flexural strength and deflection have

been proposed and the predicted results compared with test results. Load factors based on

limiting deflection and limiting crack width are also examined. Paramasivam [4] et.al., carried

out the research, to assess the flexural behavior of ferrocement slabs made up of cellular

mortar matrix was investigated for possible use as a partial or non-load bearing elements in

precast building construction. They studied on variables such as the thickness of the slab, the

number of layers of wire mesh and density of mortar are considered to study the cracking

behaviour of ductility and ultimate strength of slabs. The effect of inclusions of various

volume fractions of short steel fibers was also included in the test programme. Singh [5] et.al.,

carried out the research to assess the salient features of filler block roofing system, developed

at the institute which are non – autoclaved; compared to other types of cellular concrete

material available in the country. Hence, use of heavy equipment and machinery and high

capital investment for autoclaving are avoided. As the blocks need only curing under

atmospheric conditions, the considerable amount of energy is saved. Utilization of fly ash in

large quantities for the production of blocks is a major advantage. Therefore, there is a saving

in cement, steel and overall cost of construction, compared to conventional in-situ RC slabs

for floors and roofs Ambalavanan[6] et.al., carried out research on the effective analysis of

alternate one – way floor/roof systems. They did a systematic cost-effectiveness analysis of

one – way slabs with filler blocks and partial prefabrication system and the results are

compared with that of conventional R.C. slab. The study is aimed at assessing the relative

structural performance of alternate roof/floor slab systems adopting limit state design concept

with a view of evolving design tables to serve as a ready reckoner for designers. A

comparison of the relative cost and reduction in self – weight of these systems has been made

for establishing their range of applicability. Jaising [7] et.al., carried out research on A R.C

filler slab with non – autoclaved cellular concrete blocks for sustainable construction. In this

work, explained about construction technique of the floor/roof cast in situ RC filler slab with

non – autoclaved cellular concrete filler blocks. The filler blocks are 110mm thick and 260 x

560 mm at the top tapering down to 250 x 550mm at the bottom. The slab is cast with cement

concrete of grade M15. Spanning in two perpendicular directions, the slab can be designed as

a grid with compression taken by the deck concrete at top and tension taken by the

reinforcement at the bottom of the rib portion. The cellular concrete blocks act as non –

structural fillers. The technique can be adopted for floor/roof in single and multistoried

residential and other types of buildings. Sheela[8] et.al., carried out research on the ductile

behaviour of optimized Ferro cement corrugated flexural elements. In this investigation, an

attempt was made to obtain an optimum cross section of the polymer modified corrugated


Reinforcement


Ferro cement element by an efficient optimization technique like genetic Algorithm. The

study reveals that the engineering properties such as energy absorption capacity, ductility, and

cracking characteristics of corrugated element can be enhanced with the increase of polymer

content and volume fraction of reinforcement. In this experimental work, a total of 75

numbers of 3m length corrugated shaped specimens were prepared in the laboratory.

Adequate care was taken while placing the reinforcement cage over the mould to maintain a

minimum cover of 3mm on all sides of the specimen. Reinforcement cage consists of layers

of 6 x 22 gauges or 4 x 20 gauge wire mesh with 6 mm skeletal steel bars at junctions, where

the mesh changes its direction and is tied well together with the wire mesh. Hand plastering

was done for preparing the specimen with and without polymer modified cement sand mortar

of ratio 1:2. The specimens were removed from the mould after 2 days wet jute curing and

were cured for 28 days by ponding water on the specimen. During testing it was observed that

after first crack load for each increment of load, a number of smaller cracks were formed on

the flexural zone. Out of these only one crack widened to its maximum width and the

specimen failed at maximum load. Deflection is less in specimens having 6 x 22 gauge wire

meshes than 4 x 20 gauge wire mesh in lower loads and deflection is more at higher loads.

Sheela[9] et.al., carried out research on predicting the ultimate load carrying capacity of

polymer modified Ferro cement flexural elements. This paper reports the flexural behaviour

and ultimate load carrying capacity of ferro cement flexural elements having a span of 3m.

The investigation was for i) two cross-sectional shapes: channel and trapezoidal ii)mixes with

and without styrene butadiene rubber (SBR) iii) woven wire mesh of 4 x 20 gauge and 6 x 22

gauge and iv) the number of Wire mesh layers. The results indicate that the addition of

polymer in the mortar matrix and the use of 4 x 20 gauge wire mesh, instead of 6 x 22 gauge

wire mesh, significantly increased the load carrying capacity of the elements. A method for

predicting the ultimate load carrying capacity of the ferro cement flexural elements is also

proposed. YavuzYardim [10] et.al., Investigated on AAC – concrete light weight precast

composite floor slab. In this study, the use of autoclaved Aerated Concrete (AAC) as an in fill

material for semi precast panel is investigated experimentally. The effectiveness of proposed

light weight slab is reached by comparing the behavior of specimens with that of conventional

solid precast slab. The comparisons were based on structural performance and total weight

reduction. The composite AAC slabs section chosen are one way slabs with a size of 1m x 3m

x 0.13m (width x Length x Depth). The specimens vary in the AAC blocks layouts and total

weight reduction ratio. The test results showed that the AAC composite precast panel

provides reasonable weight reduction without sacrificing the structural capacity. Ganesan[11]

et.al., carried out research on the effect of steel fibre on the flexural behaviour of simply

supported one way SCC slabs. A total number of nine specimens were cast and tested with

steel fibers of aspect ratio of 50 and Volume fraction of 0 %, 0.5 % and 0.75 %. The load

deflection characteristics, first crack load, ultimate load, crack propagation and widening of

cracks were investigated. Addition of fibers enhanced the first crack load and post cracking

behaviour. A marginal improvement in the ultimate strength was observed. Ductility and

toughness characteristics improved significantly due to the fiber addition. GeethaKumari[12]

et.al., Investigated on Flexural Characteristics of SFRSCC and SFRNC one way slabs. In the

present study, a total number of 20 slabs of size (1050 x 500 x 65) mm were cast and tested

under flexure. Out of 20 slabs, 10 slabs were cast using steel fibre reinforced Normal concrete

(1.0 % Vf) and 10 steel slabs (1.0 % Vf). The grade of concrete used was M40 and M70. Five

different variations of tensile reinforcement were considered for SFRNC and SFRSCC. An

attempt has been done to produce M40 and M70 grade of SFRSCC reinforced slabs. Under

flexure, cracking load, ultimate load, mid-span deflections, the width of crack, strain in steel

reinforcement using strain gauge were measured during the testing of specimens. Literature



survey reveals that the information available on micro reinforcement in cost effective slab

system is not reported. Therefore it is proposed to study on the micro reinforcement roofing

system.

3. SCOPE AND OBJECTIVE OF THE STUDY

The conventional reinforced concrete slab has two basic inefficiencies i.e. a typical 125 mm

thick slab weighs 2.94kN/M2. This is to be designed for the live load of 1.96 kN/m

2. This

becomes a design load of 4.90 kN/m2 and self-weight is 60 %, therefore, the structural

efficiency of the RCC slab is only40 %. The concrete in tension zone hardly takes ant stress

as the concrete is a week in tension and becomes expensive as concrete is not resisting any

tension load. Keeping in view the above two facts, the present study has been taken up. The

proposed roofing system with micro reinforcement consumes very less quantity of materials

and becomes cost effective. This becomes conservation of materials such as fine and coarse

aggregate which are scare. However this type of roofing system depends on several factors

that require investigations. Therefore it is proposed to study on micro reinforced roofing

system and the following objectives are set.

To investigate the basic properties of materials used in the micro reinforced

roofing system.

To cast the micro reinforced roofing system with different combination of

reinforcement cage

To test the micro reinforced roofing system with suitable loading frame

To investigate the load-deflection behaviour of micro reinforced roofing system

having different types of reinforcement cages under flexure.

To determine the failure load and ultimate deflection of micro reinforced roofing

system subjected to flexure.

To evaluate equivalent uniformly distributed load [EUDL] carrying capacity of

different types of a micro reinforced roofing system.

4. EXPERIMENTAL MODEL

An experimental investigation is conducted on five test specimens. All five test specimens are

of same cross-sectional dimensions of length or span 3300mm, width 600mm and varying

depth, i.e.100mm depth at rib or beam portion and 50mm depth at slab portion.

The size of micro reinforcement /micro-truss is 3300mm x 50mm x 100 mm (LxWxH).

Reinforcement of micro truss consists of two number of 3mm diameter wire at the bottom and

2 number of 3mm diameter wire at the top. Top and bottom reinforcement are connected by

using rectangular shape stirrups spaced at 300mm c/c throughout.

Each test specimen consists of two long ribs of dimension 3300mm x 50mmx 100mm

(LxWxH) and seven short ribs of dimension 600mmx 50mm x100mm. Reinforcement

arrangement in long and short ribs is common in all five test specimen as shown in Fig1 and

2. In slab portion of the test specimen, different types of meshes are used as reinforcement.


Reinforcement


Figure 1 Dimensions of experimental model

Figure 2 Micro-truss reinforcement details

The experimental studies and research were carried out to determine the ultimate load,

load-deflection characteristics, and equivalent UDL.

The first type specimen is named as side braced rectangular micro-truss slab with

expanded metal mesh and designated as SREMTS. The expanded metal mesh is wrapped

around micro reinforcement and the same mesh is used as reinforcement in slab portion.

The second type test specimen is proposed with galvanized iron mesh. The same mesh is

used as reinforcement in slab portion and is wrapped around micro reinforcement. The test

specimen is named as side braced rectangular micro-truss slab with galvanized iron mesh and

it is designated as SRGMTS

The third type test specimen is named as side braced rectangular micro-truss slab with

chicken mesh and is designated as SRCMTS. The chicken mesh is wrapped around micro

reinforcement and the same mesh is used as reinforcement in slab portion

The fourth type test specimen is named as side braced rectangular micro-truss slab with

fiber mesh and it is designated as SRFMTS. Fiber mesh is used as reinforcement in slab

portion and the same mesh is wrapped around the micro reinforcement

The fifth type test specimen is designated as SRWMTS. In this test specimen, 3mm

diameter wire is placed at 150mm c/c in both directions as reinforcement in slab portion.

Figure 3 Types of Mesh



Figure 4 Experimental Model

Table 1 Reinforcement Details of Test Specimens

NO Slab

Designation

Reinforcement in Slab Portion

Reinforcement in Rib Portion

1 SREMTS EM * MR* + EM

2 SRGMTS GM* MR + GM

3 SRCMTS CM* MR + CM

4 SRFMTS FM* MR + FM

5 SRWMTS

3mm diameter Wire placed at 150mm c/c in both directions

MR

5. MATERIALS USED

The following materials are used in casting Micro truss reinforcement slab.

1. Cement

2. Coarse aggregate

3. Fine aggregate

4. Mixing Water

5. Types of meshes (Expanded Metal, Galvanized Iron, Chicken, Fiber mesh)

6. 3mm diameter Mild steel wire

Cement: Ordinary Portland Cement (OPC) 43 grade was used in the study. All tests were

carried out in accordance with BIS 8112-1989, BIS 269-1967 and BIS 12269. The test results

are in confirmation with BIS.

Coarse aggregate: Locally available crushed granite was used. As the thickness of slab

and size of the beams are lesser than the normal slab size, the coarse aggregate used is passing

through 12.5mm and 4.75mm retained. Various tests were conducted to determine specific

gravity and fineness modulus of the aggregates. The tests were carried out in accordance with

the stipulations laid by BIS 650-1966 and BIS 2386. The test results are in confirmation with

BIS.

Fine aggregate: Locally available river sand was used as fine aggregate. It confirmed to

BIS 383 – 1970. Sand confirming to Zone - II

Water: Fresh and clean water was used for casting and curing the specimens. The water

used was free from suspended particles and organic materials

Types of Meshes: Expanded metal mesh, Fiber Mesh, Chicken Mesh and Galvanized Iron

Mesh with 12.5 mm grid size have been used as primary reinforcement in slab portion of the

test specimen.

3mm diameter Mild steel wire: 3mm diameter mild steel wire is used in fabricating micro

reinforcement.

EM Expanded Metal Mesh

GM Galvanized Iron Mesh

CM Chicken Mesh

FM Fiber Mesh

MR Micro Reinforcement


Reinforcement


6. CASTING OF TEST SPECIMENS

Totally five numbers of test slab panels were cast for different combinations reinforcement

cage. Cross-sectional dimension of the test specimen is 3300mm x 600mm x 100mm to

50mm (100mm depth at rib portion and 50mm depth at slab portion). Step by step procedure

for the casting of a test specimen is follows

Step-1: Sheet of papers was laid on the leveled platform to avoid the concrete coming in

contact with the floor base.

Step-2: The inner surface of the mould is oiled and placed on a smooth leveled surface.

Before placing reinforcement cage, 10mm thick one layer of concrete is laid and compacted.

Step -3: After laying a layer of 10mm thick concrete cover, reinforcement cage is placed.

Concrete is filled in the mold up to a depth of 50mm and leveled and the concrete is

compacted.

Step-4: The inner mold was placed, and concrete was filled in the space between the mold

parts and rib thickness is maintained to 50mm. the overall depth is maintained to 100mm at

main and cross beam portion. 50mm depth is maintained at slab portion of the test specimen.

After 8 hours of casting, test specimen were demolded and cured for 28 days. In a similar

way, all remaining slabs were cast.

Figure 5 Casting of Test Specimens

7. EXPERIMENTAL SETUP

The experimental setup consists of loading frame of 500 kN capacity. The load was applied

by means of a load cell of 100 kN capacity. All the specimens were tested by simulating

simply supported conditions. The test slabs were painted using whitecem to help in tracing the

developing cracks on slabs. After completing all initial arrangements, the load is applied using

hydraulic jack mounted on reaction frame. Uniform rate of loading is applied on test slab and

it is transferred uniformly to four points on test slab through four-point loading frame. For

each 20kg increment of load, deflections are recorded from LVDT. Load VS deflection plot

has been made for all five test slabs. The experiment is continued till first crack load, ultimate

load, and breaking load were recorded. Loading is kept continuous till failure. The breaking

pattern and the type of failure of the slab are noted.

Figure 6 Loading arrangements Figure 7 Slab over testing platform



8. EXPERIMENTAL RESULTS

The testing of micro reinforcement slab was done under the four-point loading to create

flexural effect. Comparative study of different reinforcement combination of micro

reinforcement slab was carried out with respect to crack pattern, equivalent UDL at first crack

load and collapse load stage. The span of the test slab was 3300mm (Span). The load was

increased at regular intervals and the deflection was noted at the L/3 distance of the test

specimen. After observing Load Vs deflection results of five test specimens, the test results

are reported in Table 2 and Table 3. Load VS deflection results are shown in Fig 8 to Fig 12.

Table 2 First Crack, Collapse load and deflection of micro truss reinforced slab system S

I.N

O

Sla

b D

esi

gn

ati

on

Fir

st C

rack

Lo

ad

(k

N)

Def

lect

ion

(m

m)

Co

lla

pse

Lo

ad

(kN

)

Def

lect

ion

(m

m)

1 SREMT

S 2.8 4.4 7.8 22.3

2 SRGMT

S 3.6 14.5 5.4 54.1

3 SRCMT

S 2.8 3.8 5.0 18.4

4 SRFMTS 2.0 2.5 4.4 9.8

5 SRWMT

S 2.8 12.5 5.6 52.9

Table 3 Equivalent UDL at First crack and Collapse Load

SI.

NO

Sla

b D

esi

gn

ati

on

Eq

uiv

ale

nt

UD

L a

t F

irst

C

rack

Lo

ad

( K

N /

m

2)N

/)

Eq

uiv

ale

nt

UD

L a

t C

oll

ap

se L

oa

d (

KN

/ m

2)

1 SREMT

S 1.41 3.93

2 SRGMT

S 1.81

2.72

3 SRCMT

S

1.41 2.52

4 SRFMTS 1.01

2.22

5 SRWMT

S 1.41 2.82


Reinforcement


Figure 8 Load Deflection Curves for Slab, Main Beam, and Cross Beam portion of Slab SREMTS

Figure 9 Load Deflection Curves for Slab, Main Beam and Cross Beam portion of Slab SRGMTS

Figure 10 Load Deflection Curves for Slab, Main Beam, and Cross Beam portion of Slab SRCMTS

Figure 11 Load Deflection Curves for Slab, Main Beam, and Cross Beam portion of Slab SRFMTS



Figure 12 Load Deflection Curves for Slab, Main Beam, and Cross Beam portion of Slab SRWMTS

9. DISCUSSION ON EXPERIMENTAL RESULTS

The load deflection measurements were resulted in the four point loading flexural test on the

micro reinforced specimens having different types of micro reinforcement. First crack vs.

deflection and collapse load vs deflection results are reported in Table -2. Equivalent

uniformly distributed load at First crack and at collapse load is tabulated in Table-3.

Following discussion is made on the effect of different types of micro reinforcement on the

five test specimens.

9.1. First Crack loads and collapse loads & Equivalent UDL

First crack appeared in test specimen SREMTS at 2.8 kN whereas collapse occurred in

test specimen at 7.8kN at the age of 28 days. Equivalent UDL at collapse load was

recorded 3.93 kN / m2.

Similarly from flexural test results reveals that First crack appeared in test specimens

SRGMTS, SRCMTS, SRFMTS and SRWMTS at 3.6kN, 2.8kN, 2.0kN and 2.8kN

whereas collapse occurred in all four test specimens at 5.4kN, 5.0kN, 4.4kN and

5.6kN. at the age of 28 days

Equivalent UDL at collapse load in test specimens SRGMTS,SRCMTS,SRFMTS

and SRWMTS was recorded 2.72kN/m2, 2.52kN/m2 , 2.22 kN/m2 and 2.82 kN/m2.

Equivalent UDL at collapse load in test specimens SRGMTS,SRCMTS,SRFMTS

and SRWMTS was recorded 2.72kN/m2, 2.52kN/m2 , 2.22 kN/m2 and 2.82 kN/m2.

9.2. Load Deflection Behavior

Variation of load and deflection test results are graphically represented Figure 8 to 12.Test

results revels that, test specimens SRGMTS and SRWMTS shows 14.5mm and 12.5mm

deflection at First crack. This deflection is slightly higher than permissible deflection. But

remaining test specimens SREMTS, SRCMTS and SRFMTS shows deflection within

permissible limit.

10. CONCLUSION

Based on the experimental results of theses test specimens, following conclusions can be

drawn

Equivalent UDL carrying capacity of test specimens SREMTS, SRCMTS is 1.41

kN /m2 at First crack whereas 3.93 kN/m2 and 2.52 kN/m2 at collapse load and

deflection is slighter higher compared to permissible deflection.

In Micro reinforced cost effective slab system 20% Economy can be achieved

when compared with conventional roofing system.


Reinforcement


REFERENCES

[1] P.M. Abdul Rahman and H.G. Sreenath .,” Precast prestressed concrete slab incorporating

structural hollow clay blocks in floors and roofs”., Indian concrete journal, May 1975, PP

134-138

[2] B.D Sharma, Design and construction of precast hollow or ribbed slab. Indian concrete

Journal, January 1980, pp 15-20.

[3] P.Desayi, C.S. Viswanath, S. Kanappan, Some studies on Ferro cement roofing elements.,

Journal of Ferrocement, Vol 12, No 3, July 1982, PP 273-286.

[4] P. Paramasivam, M.A. Mansur, Ong K.C., Flexural Behaviour of Light weight

Ferrocement Slabs., Journal of Ferrocement, Vol 15 , No -1, January 1985, PP 25-30

[5] M.P. Jaising, lathika Jaising, M. Khalid, S.P Tehri, and Bhupal Singh., A RC filler slab for

Floors and roofs with non – autoclaved cellular concrete blocks, The Indian Concrete

Journal, March 1997, PP 152-155.

[6] Dr. R . Ambalavanan, N. Narayanan, Dr. K. Ramamurthy., cost – effectiveness analysis of

alternate one – way floor / roof system, The Indian Concrete Journal, March 1990, PP

171-177.

[7] M.P.jaising, L. jaising, B. sing., A R.C filler slab with non – autoclaved cellular concrete

blocks for sustainable construction, published by central building research Institute,

Roorke, India.

[8] S.Sheela, N. Ganesan., Ductile Behavior of optimized ferrocement corrugated flexural

elements, Journal of structural Engineering, Vol 39, No -4 oct-nove 2011 PP 333-344.

[9] S. Sheela, N.Ganesan., “ Predicting the ultimate load carrying capacity of polymer

modified ferrocement flexural elements “, The Indian Concrete Journal, November 2012,

PP 43 – 51

[10] Yavuz Yardim, A.M.T. Waleed, Mohd salem jaafar, Saleh Laseima., “ AAC – Concrete

light weight precast composite floor slab “, Construction and Building Materials - 2013,

PP 405-410.

[11] N.Ganesan, V. Syamprakash , Mini Soman., “ Behaviour of Steel fibre reinforced self

compacting concrete one way slabs “, Journal of structural Engineering, Vol 40, No2,

JULY 2013, PP 104-112

[12] T.Geetha Kumari, C.G.Puttappa., C.Shashidar, K.U.Muthu., “ Flexural Characteristics of

SFRSCC and SFRNC one way slabs “, International journal of Research in Engineering

and Technology, Volume 02, July 2013 PP 220 – 229

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