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Ferro cement The term Ferro cement is most commonly applied to a mixture of Portland cement and sand applied over layers of woven or expanded steel mesh and closely spaced small-diameter steel rods. It can be used to form relatively thin, compound curved sheets to make hulls for boats, shell roofs, water tanks, etc. It has been used in a wide range of other applications including sculpture and prefabricated building components. The term has been applied by extension to other composite materials including some containing no cement and no ferrous material. These are better referred to by terms describing their actual contents.
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FLEXURAL BEHAVIOUR OF STEEL FIBRE
REINFORCED AND LATEX MODIFIED
FERROCEMENT SLABS
BY
ABRAHAM JAMES FINNEY
DIVYA RUBAN
SANTHOSH KUMAR
GOVINDARAJ
Project guide
Mr.S.Sivachandran
Asst professor
Civil department
FERROCEMENT
Mixture of portland cement and sand applied over
layers of woven or expanded steel mesh
Desired shape can be built.
Economical.
Lesser cross sectional area.
Relatively thin, compound curved sheets to make
hulls for boats, shell roofs, water tanks, etc
LATEX
• Latex -carboxylate styrene butadiene copolymer.
• Improves bond strength.
• Increases flexural & compression strength
• Enhances impact strength.
• Resistance to hydrolysis.
MICRO STEEL FIBER
• Increases structural integrity.
• It contains short discrete fibers that are uniformly
distributed and randomly oriented.
• Controls cracking.
• They also reduce the permeability of slab.
• It produce greater impact, abrasion, and shatter–
resistance in concrete.
Ferrocement structure
Micro Steel FibreThe Process of cutting the Welded mesh
Construction of a Ferrocement tank
OBJECTIVES
To identify various ingredients used for Ferrocement slabs.
Preliminary study on properties of materials used in this project.
Mix design of cement : sand ratio is 1:2.
Comparison of mechanical properties of steel fibre reinforced
cement mortar Ferrocement slabs and latex modified reinforced
cement mortar Ferrocement slabs.
Comparison of Strength between two types of Ferrocement
slabs by adding different layers of welded mesh.
Analysis of test results and arrive conclusions.
METHODOLOGY
Literature review on Ferrocement slabs.
Study of codal provisions.
Collection of welded mesh, steel fibres, latex and other ingredients.
Preliminary tests on materials.
Design of mortar mix.
Casting of the Ferrocement slabs.
Flexural strength and the mechanical properties such as ductility,
toughness and energy of all specimens to be calculated.
Analysis of the test results.
Comparison of the results obtained.
Conclusion.
APPLICATIONS OF FERROCEMENT ELEMENTS
Strengthening of RC Beams using Ferrocement
Laminates
Water Tanks
Secondary Roofing Slabs
Sunscreens
Hulls of boats
sculptures
MATERIALS SPECIFICATION
Cement: Portland Pozzolanic Cement of grade53
Fine aggregate: Ordinary river sand sieve of size
2.36 .
Mortar: Cube specimens of size 70 mm x 70 mm x
70 mm
Micro Steel fibres : length 13mm,dia 0.15mm
Steel Mesh: Diameter 1mm, grid size 1 X 1 cm.
DESIGN OF FERROCEMENT SLABS
No. of
speci
mens
Name of The
Specimen
No of layers of welded
meshes
Size of the slab
(mm)
Cement: Sand
Mix ratio
1 A1 4 600 × 300 1:2
1 A2 6 600 × 300 1:2
1 A3 8 600 × 300 1:2
Batch A-Steel fibre reinforced cement mortar Ferrocement slab
Weight of the cement = 20 kg
Weight of sand = 40 kg
Weight of water = 4.7 litre
Weight of steel fibres = 2 kg
Weight of the 4 layered mesh, A1 = 444gm
Weight of the 6layered mesh, A2 = 712gm
Weight of the 8 layered mesh, A3 = 1.045 kg
The total weight of the 4 layered slab = 9.55 kg
The total weight of the 6 layered slab = 11.36 kg
The total weight of the 8 layered slab = 11.85 kg
Batch A- Steel fibre reinforced cement mortar Ferrocement slab
BATCH B: LATEX MODIFIED STEEL FIBRE
REINFORCED FERROCEMENT SLAB
No. of
specimens
Name of The
Specimen
No of layers of welded
meshes
Size of the slab
(mm)
Cement:Sand
Mix ratio
1 B1 4 600 × 300 1:2
1 B2 6 600 × 300 1:2
1 B3 8 600 × 300 1:2
Batch B
Weight of the cement = 20 kg
Weight of sand = 40 kg
Weight of water = 2.82litre
Weight of steel fibres = 2 kg
Weight of the latex = 950ml
Weight of the 4 layered mesh, B1 = 444gm
Weight of the 6layered mesh, B2 = 712 gm
Weight of the 8 layered mesh, B3 = 1.045 kg
The total weight of the 4 layered slab = 12.01 kg
The total weight of the 6 layered slab = 12.25 kg
The total weight of the 8 layered slab = 12.40 kg
TESTS ON MORTAR CUBE
The mix proportion of the mortar cube
Cement : sand : water ratio : 1 : 2 : 0.47
S.no Days Compressive Strength (MPa)
1 0 0
2 3 21.50
3 7 23.01
4 28 33.22
Compressive Strength of mortar specimens
COMPRESSIVE STRENGTH DEVELOPMENT CURVE FOR
MORTAR CUBE
TESTING OF FERROCEMENT SLABS
Casting of the slabs specimen
Curing
Preparation for test specimens
Flexural test on Ferrocement slabs
Specimen placed in closed mould
Casting of the slabs specimen
Deflectometer placed on the Ferrocement
slab specimen
The specimens are subjected to flexural
strength test using UTM machine
DEFORMATION AND CRACKING BEHAVIOR OF
SLABS UNDER FLEXURAL LOADING.
Slab
I.D
First
Cracking
load
(KN)
1ST
cracking
central
deflection
(mm)
No of
cracks at
first crack
Spacing
at first
crack
(mm)
Ultimate
load
(KN)
Ultimate
load
Deflection
(mm)
No of
cracks at
ultimate
load
Crack
spacing at
ultimate
load
(mm)
A1 4 3.53 5 220 5.6 13.44 54 10
A2 4 2.33 6 40 7.28 8.44 32 20
A3 4.4 2.34 2 40 10.08 16.49 26 10
B1 3.2 4.21 7 30 5.6 13.01 23 15
B2 2 1.99 6 30 5.68 8.5 17 25
B3 3 2.15 5 30 8.4 16.64 30 15
0
1
2
3
4
5
6
0 5 10 15
Lo
ad
(K
N)
Deflection (mm)0
1
2
3
4
5
6
7
8
0 2 4 6 8 10
Lo
ad
(K
N)
Deflection (mm)
0
2
4
6
8
10
12
0 2 4 6 8 10 12 14 16 18
Lo
ad
(K
N)
Deflection (mm)
Batch A
A1 A2
A3
0
1
2
3
4
5
6
0 5 10 15
Lo
ad
(K
N)
Deflection (mm)
0
1
2
3
4
5
6
0 5 10 15 20
LO
AD
(Kn
)
DEFLECTION(mm)
0
1
2
3
4
5
6
7
8
9
0 5 10 15 20
LO
AD
(K
N)
DEFLECTION(mm)
Batch B
B1
B3
B2
FLEXURAL STRENGTH
FORMULA USED
R = P*L / b*𝑑2
NO OF LAYERS FLEXURAL STRENGTH
(Kn/m2)
BATCH A BATCH B
4 1.4388 1.5476
6 1.7384 2.1384
8 2.4355 4.1362
ENERGY ABSORPTION CAPACITY
No of layers Batch A
(KN mm)
Batch B
(KN mm)
4 2.62 2.823
6 4.977 5.83
8 5.22 6.15
ENERGY = AREA UNDER THE LOAD DEFLECTION CURVE
COMPARISON OF ENERGY ABSORPTION
CAPACITY
0
1
2
3
4
5
6
7
8
1 2 3 4
No of layers
Ferro- steel fibre (J/sec)
Ferro-latex and steel fibre (J/Sec)
CALCULATION OF DUCTILITY VALUE
No of layers Batch A Batch B
4 1.4 1.875
6 1.82 2.84
8 2.7 3.36
Ductility = Ultimate load / First cracking load
Formula used
COMPARISON OF DUCTILITY VALUE
0
200
400
600
800
1000
1200
1400
1 2 3 4
No of layers
Ferro- steel fibre
Ferro-latex and steel fibre
CALCULATION OF TOUGHNESS VALUE:
No of layers Batch A Batch B
4 382.86 589.83
6 628.31 1026.02
8 1180.33 1337.55
Toughness = Total area of the curve/ area up to first crack obtained curve.
COMPARISON OF TOUGHNESS VALUE:
0
200
400
600
800
1000
1200
1400
1 2 3 4
No of layers
Ferro- steel fibre (mm)
Ferro-latex and steel fibre (mm)
RESULTS
Specimen Flexural
strength
Energy
absorption
value
Ductility Toughness
B1>A1 7.69 % 7.75 % 33.9% 54.05%
B2>A2 23.82 % 17.14% 56.04% 63.21%
B3>A3 69.95 % 17.82% 24% 13.32%
The below table shows the increase in percentage of the Flexural strength
and mechanical properties of Latex modified Steel fibre reinforced
ferrocement slabs over Steel fibre reinforced ferrocement slabs
CONCLUSION
Thus from the above comparison it is evident that the
latex modified steel fibre reinforced cement mortar
Ferro cement slabs of 4, 6 and 8 layers are having a
greater flexural strength and mechanical properties.
Thank You
