b.tech final year seminar report on ferrocement in civil engineering

1. A
Seminar Report on
Ferro-Cement
Submitted to
Rajasthan Technical University, Kota
In partial fulfilment for
The award of degree of
Bachelor of Technology (B. TECH)
Department of Civil Engineering
Govt. Engineering College
Ajmer-305001
SUBMITTED BY: PROJECT GUIDE: -
VEDPRAKASH JANGID (15CE57) Mr. DHARMENDRA SINGH DHAKA

2. i
Candidate’s Declaration
I hereby declare that the work, which is being presented in the seminar entitled “Ferro-cement”
in partial fulfilment for the award of Degree of “Bachelor of Technology” in Department of Civil
Engineering with Specialization in Civil Engineering and submitted to the Department of Civil
Engineering, Government Engineering College, Ajmer, Rajasthan Technical University is a
record of my own investigations carried under the Guidance of Mr. Dharmendra Singh Dhaka,
Department of Civil Engineering, Government Engineering College, Ajmer.
I have not submitted the matter presented in this report anywhere for the award of any other
degree.
Govt. Engineering College, Ajmer

3. ii
Certificate
This is to certify that Vedprakash Jangid of VIII Semester, Bechlor of Technology (Civil
Engineering) 2018-19, has presented a seminar entitled “Ferro-cement” in partial fulfilment for
the award of the degree under Rajasthan Technical University, Kota.
Date:
Place:
Dr. Ganpat Singh
Head of Department
Mr. Dharmendra Singh Dhaka Mr. Anurag Kumar Singh
Seminar Guide Seminar Co-ordinator

4. iii
Abstract
Ferro-cement is a composite material made up of cement mortar and reinforced in the form of
layer of mesh. This composite material is a form of cement material that behaves differently
from reinforced concrete. There is some similarity between the Ferro-cement materials and
reinforced concrete. These differences are indicating that Ferro-cement requires a separate study
to establish its structural performances. Ferro-cement which is a thin element, is used as a
building construction as well as repairing materials. This review from the past experience present
the analytical studies on Ferro-cement members, results of experimental and bring out the salient
features of construction, material properties, the special techniques of applying cement mortar on
to the reinforcing mesh. This study brings out the importance of using Ferro cement in water
tanks and swimming pools, silos, corrugated roofs, slab panels, dome structures and shell by
using available mechanized production methods and proper choice of reinforcements.

5. iv
Acknowledgment
I take this opportunity to express my gratitude to all those people who have been directly and
indirectly with me during the competition of this seminar.
I pay thank to Dr. Ganpat Singh, Head of Department of Civil Engineering, who gave me this
opportunity to give a seminar on “Ferro-cement”
I pay thank to Mr. Dharmendra Singh Dhaka who has given guidance and a light to me during
this seminar. His versatile knowledge about “Ferro-cement” has eased me in the critical times
during the seminar.
A special gratitude I give to our final year seminar co-ordinator, Mr. Anurag Kumar Singh,
whose contribution in stimulating suggestions and encouragement, helped me to coordinate my
seminar especially in writing this report.
My thanks and appreciations also go to my colleague and college staff in preparing seminar
report and people who has willingly helped me out with their abilities.
Thank you
Vedprakash Jangid
B. Tech Final Year
(Civil Engineering)

6. v
Contents
Candidate’s Declaration................................................................................................................... i
Certificate........................................................................................................................................ii
Abstract.......................................................................................................................................... iii
Acknowledgment............................................................................................................................iv
CHAPTER 1: INTERODUCTION................................................................................................. 1
1.1 Definition of Ferro Cement...............................................................................................1
1.2 Ferrocement Trends.......................................................................................................... 2
CHAPTER 2: LITERATURE REVIEW.........................................................................................4
CHAPTER 3: MATERIAL USED IN CONSTRUCTION.............................................................7
3.1 Cement Mortar Matrix...................................................................................................... 7
3.2 Cement.............................................................................................................................. 7
3.3 Sand or Fine Aggregate.....................................................................................................7
3.4 Water/Cement Ratio..........................................................................................................7
3.5 Cement/Sand Ratio............................................................................................................8
3.6 Reinforcement...................................................................................................................8
3.6.1 Skeleton Steel............................................................................................................ 8
3.6.2 Wire Mesh..................................................................................................................9
CHAPTER 4: CONSTRUCTION OF FERRO-CEMENT........................................................... 10
4.1 Hand Plastering...............................................................................................................11
4.2 Semi Mechanised Process...............................................................................................12
4.2.1 Advantage of Semi Mechanised Method.................................................................13
4.3 Centrifuging Method.......................................................................................................14

7. vi
4.4 Guiniting......................................................................................................................... 15
CHAPTER 5: PROPERTIES OF FERROCEMENT....................................................................16
5.1 Impact Resistance............................................................................................................16
5.2 Crack Development and Leakage................................................................................... 16
5.3 Shrinkage and Creep....................................................................................................... 16
5.4 Compressive Strength..................................................................................................... 17
5.5 Tensile Strength.............................................................................................................. 17
5.6 Fatigue Strength.............................................................................................................. 17
CHAPTER 6: ADVANTAGES AND DISADVANTAGES........................................................18
6.1 Advantages......................................................................................................................18
6.2 Disadvantages................................................................................................................. 18
CHAPTER 7: APPLICATIONS OF FERROCEMENT...............................................................20
CHAPTER 8: NEED TO STUDY................................................................................................ 23
CHAPTER 9: CONCLUSION......................................................................................................25

8. vii
Table of Content
Figure 1.1 - A Section of Ferrocement Section............................................................................... 1
Figure 3.1 - Wire Mesh for Ferro-Cement Structure.......................................................................9
Figure 3.2 - Hexagonal and Welded Wire Mess..…………………………………………………9
Figure 3.3 - Woven Wire Mess........................................................................................................9
Figure 4.1 - Hand Plastering..........................................................................................................11
Figure 4.2 - Semi Mechanised Process of Plastering.....................................................................13
Figure 4.3 - Guniting..................................................................................................................... 14
Figure 6.1 - Ferro-Cement Tank....................................................................................................20
Figure 6.2 - Ferro-Cement Boat.....................................................................................................21
Figure 6.3 - Ferro-Cement Pressure Pipes.....................................................................................21
Figure 6.4 - Ferro-Cement Bench..................................................................................................22

9. 1
CHAPTER 1
INTRODUCTION
1.1 Definition of Ferro Cement
“Ferro cement is a type of thin wall reinforced concrete, commonly constructed of hydraulic
cement mortar, reinforced with closely spaced layers of continuous and relatively small size wire
mesh. The mesh may be made of metallic or other suitable materials”. Ferro- means iron and the
metal commonly used in ferro-cement is the iron alloy steel. It consists of closely spaced,
multiple layers of mesh or fine rods in cement mortar. A composite material is formed and it
behaves differently from conventional reinforced concrete in strength, deformation, and potential
applications. So, it is classified as a separate and distinct material.
It can be formed into thin panels, less than 1 inch (25 mm) thick, with only a thin mortar cover
over the outermost layers of reinforcement. There are many characteristics of ferrocement that
can be achieved with reinforcement other than steel meshes or rods. The use of non-metallic
mesh is being explored in several universities. Such meshes include woven alkali resistant glass,
organic woven fabrics and organic natural fabrics made with jute, or bamboo fibers.
Figure 1.1- A Section of Ferrocement Section

10. 2
The following definition was adopted by the ACI Committee: “ferrocement is a type of thin wall
reinforced concrete commonly constructed of hydraulic cement mortar reinforced with closely
spaced layers of continuous and relatively small size wire mesh. The mesh may be made of
metallic or other suitable materials.”
1.2 Ferrocement Trends
Widespread use of ferrocement in the construction industry has occurred during the last 35 years,
The main applications of ferrocement construction to date have been for silos, tanks, roofs, and
mostly for boats.
The construction of ferrocement can be divided into four phases:
1. Fabricating the steel rods to form a skeletal framing system
2. Tying or fastening rods and mesh to the skeletal framing
3. Plastering
4. Curing
Ferrocement has very high tensile strength to weight ratio and superior cracking behavior to
conventional reinforced concrete. This means that the thin ferrocement structures can be made
relatively light and water tight. Hence, the ferrocement is an attractive material for the
construction of boats, barges, prefabricated housing units, and other portable structures.
The inventors of ferrocement are Frenchmen Joseph Monier who dubbed it as "ciment armé"
(armored cement) and Joseph-Louis Lambton who constructed a batteau with the system in
1848. Lambot exhibited the vessel at the Exposition Universelle in 1855 and his name for the
material "ferciment" stuck. Lambot patented his batteau in 1855 but the patent was granted in
Belgium and only applied to that country. At the time of Monier's first patent, July 1867, he
planned to use his material to create urns, planters, and cisterns. These implements were
traditionally made from ceramics, but large-scale, kiln-fired projects were expensive and prone
to failure. In 1875, Monier expanded his patents to include bridges and designed his first steel-
and-concrete bridge. The outer layer was sculpted to mimic rustic logs and timbers, thereby also

11. 3
ushering Faux Bois (wood grain) concrete. In the first half of the twentieth century Italian Pier
Luigi Nervi was noted for his use of ferro-cement, in Italian called ferro-cemento.

12. 4
CHAPTER 2
LITERATURE REVIEW
Ferro-cement is commonly used as repairing & strengthening material, apart with this character
ferrocement is found to be very good solution for fire protection because of its post –fire flexural
strength and toughness with plain mortar or concrete cover. The increase in wire mesh content
significantly improved the mechanical properties of ferrocement under normal conditionsi
.
ferrocement jackets reinforced with expanded steel meshes can be used effectively to strengthen
shear deficient concrete columns. The shear strength of ferrocement jacket can be estimated by
the following simple equations given below ii
Vyf = 2 n vf tf af fyf
where,
vf = volume fraction of ferrocement reinforcement
tf = thickness of ferrocement jacket,
af = t distance between load point and edge of the jacket (a gap distance less than shear span),
n = global efficiency factor for ferrocement reinforcement (0.65 for long diagonal direction of
expanded mesh),
f yf = the yield strength of ferrocement reinforcement.
Ferro mesh plays very important role in enhancing the strength capacity and in failure mode for
preventing the sudden and brittle failure. It also increases the ductility iii
. A procedure to analyse
ferrocement slabs has been presented by Ihsan Qasim Mohamad and he also found that
Geometric nonlinear concept playsan important role in predicting the analytical results and gives
more accurate resultsiv
.The confinement can be improved with the help of ferrocement shell,
which is helpful in increasing the ultimate strength is linearly vary with the specific surface area.
Mathematically it is expressed as followsv
.
F = fc’ [(1.0 + 0.33Ci) (0.012 + 0.33Sf) Ag + fyAg]
Where,

13. 5
P = Ultimate load carrying capacity of FCRC prism section
Fc’ = Strength of unconfined concrete
Ci = Confinement index
Sf = Spacing of ferro-cement mesh
Ag = Gross cross-sectional area
Fy = Yield strength of longitudinal tie/mesh steel
As = Area of longitudinal steel
Expanded steel mesh also achieved good ductility and modulus of rupture [MOR]. MOR is
directly proportional to volume fraction and more volume fraction reduces crack spacing and
widthvi
. Double layer WWM gives nearly double strength than the single layer of WWM. There
is increase in strength with change in orientation of mesh from 90º to 45ºvii
. Ferrocement jacket
improves the axial load capacity & axial stiffness about 33% & 26% respectively. The column
repaired with ferrocement improves the ductility characteristicsviii
. High-performance
ferrocement laminate (HPFL) is new material composed of grid rebar and ordinary cement
mortar, which contained polyethylene fibre, expansion agent, water reducer, fly ash, etc. HPFL
can raise the bearing capacity of the concrete members significantlyix
. The durability of
ferrocement structures can be enhanced with the help of suitable surface coating & surface
coating will offer the best protection for the mortar and the meshx
. Ferrocement is one of the
most commonly used material due to its easy availability, durability, economy, and the ability to
mould in any require shape easily. When it is oriented with 45 degree, it gives higher percentage
of energy absorption compared to 0 & 60 degree xi
. The most common type of reinforcement
used for ferrocement is Woven wire grids with a hexagonal weave. The advantages of such
reinforcement include its relatively low cost and ease of use. The size of the openings in the grid
are varied from 10 to 25 mm and depend on the grid's characteristicsxii
.The shear strength, lateral
stiffness and the lateral load capacity of the masonry is significantly increased when retrofitted
with ferro meshxiii
. Light weight ferrocement beam have good moment of resistance capacity.
The numbers of layers of wire mesh are help full in sustaining greater number of repetitions,
strain carrying capacity, increasing the margin between first crack and ultimate flexural strength

14. 6
xiv
..The 45° orientation emerges as the weakest configuration because of the lowest volume
fraction of wire mesh in the direction of loading at this orientation.
The LWF beams exhibit better performance in achieving the improvements on pre-cracking
stiffness, load carrying capacity, energy absorption capacity, ductility index and a higher
ultimate flexural load-to-weight ratio compared with RC beamsxv
]. Post fire flexural strength and
toughness of ferrocement jacket is good in comparison with plain mortar. An increase in wire
mesh content significantly improved the mechanical properties of ferrocement under normal
conditions; however, after fire exposure the amount of wire mesh was no longer significant,
regardless of heating durationxvi
. The ferrocement was invented by Joseph Louis Lambot in 1848,
but it was used for construction elements in the beginning of the 19th century by Pier Luigi
Nervi, a famous Italian designer who wanted to have a homogeneous and efficient material for
his complex architectural shapes. The disadvantage of ferro concrete construction is the labor
intensive nature of it, which makes it expensive for industrial applicationxvii
. The shear strength
of the ferrocement plate depends upon the volume fraction of wire mesh. Hexagonal mesh
improves the shear capacity over than that of diamond and square meshes because of it having a
higher straight length xviii
.

15. 7
CHAPTER 3
MATERIAL USED IN CONSTRUCTION
Following materials are used in productions of ferrocement
3.1 Cement Mortar Matrix
It consists of a rich cement mortar which have matrix of 10 to 60 mm thickness with a
reinforcement volume of 5 to 8% in the form of one or more layers. These layers are very thin
mesh and a skeleton reinforcement consisting of mild steel bars or welded mesh.
3.2 Cement
The cement choice depends on the service conditions. The cement should be free of lumps fresh,
of uniform consistency, and foreign matter.
3.3 Sand or Fine Aggregate
Sand is an inert material. Sand occupies 60.to 75% volume in the ferro cement mortar. To impart
good properties to the mortar, it should be strong, hard, non-porous and chemically inert. It
should be free from clay, silt and other organic impurities. Particle size should not be more than
2.36 mm.
If there are particles of larger than 2.36 mm present in sufficient quantity may cause the mortar
porous if particles less than 1.18 mm are present in large quantity. They will require more water
for the required impermeability and workability, affecting the strength. Thus, the sand should be
of grading zones II and III with particles greater than 2.36 mm and smaller than 1.18 mm
removed. Fine sand in ferrocement cannot be used.
3.4 Water/Cement Ratio
As it governs the workability and strength of the mortar, it depends upon the maximum grain
size, the fineness modulus and the grading of the sand. Generally, water/cement ratio by mass
may vary between 0.60 to 0.35. In order to reduce permeability, water/cement ratio should not be

16. 8
kept above 0.40. In the calculations of required water, the moisture content of the aggregate
should be taken into account. By the use of appropriate admixtures, the amount of water many be
reduced.
3.5 Cement/Sand Ratio
Cement sand ratio may be kept 1:3or 1:2. The slump of fresh mortar should not be less than 50
mm for most works the strength of moist cured cubes should be about 350 MPa.
The matrix constitutes about 95% of the ferrocement and governs the behaviour of the final
product. Thus, proper selection of constituent materials, their placing and mixing is important.
The total volume of cement and fines should be about 300 cm3
per litre of mortar. A change in
the amount of cement must be accompanied to a corresponding change to the fines.
3.6 Reinforcement
Two types of reinforcement are used in ferrocement:
3.6.1 Skeleton Steel
The skeleton steel frame is made conforming exactly to shape of the structure and the geometry.
This is used for holding the wire mesh in shape of the structure and position. The diameter of the
steel rods is spaced at 70 to 100 mm apart and may vary from 3 to 8 mm. It may be welded wire
fabric or tied reinforcement.
The welded wire fabric is made from 3 to 4 mm diameter wires welded at 80 to 100 mm centre to
centre. These skeleton frames are used for cylindrical or other surfaces where these meshes can
be bent easily. In case where higher stresses may occur, as skeleton steel the mild steel bars are
used.
The longitudinal steel bars and spacing of transverse depends upon the shape and type of the
structure. In case of boat hulls a spacing of 100 to 75 mm is adequate, where as in water tanks,
bins etc. the spacing may vary between 200 to 300 mm. The bars may be welded or tied with the
binding wires. The reinforcement should be free from loose rust, dust, oil, coating of paints, etc.

17. 9
3.6.2 Wire Mesh
The wire mesh consists of galvanized wire spaced at 6 to 20 mm centre to centre and 0.5 to 1.5
mm diameter. The wire mesh may be of the shape as welded wire mesh or square woven wire
mesh, Hexagonal wire or mesh expanded metal etc. Generally square woven meshes consisting
of 1.0 to 1.5 mm diameter wires spaced about 12 mm are preferable. The yield strength of plain
wires used in fabric should not be more than 415 MPa and 500 MPa for deformed wires. The
steel content may vary between 300 kg to 500 kg per cubic metre of mortar.
Figure 3.1 - Wire Mesh for Ferro-Cement Structure
Figure 3.2 Hexagonal and Welded Wire Mess Figure 3.3 Woven Wire Mess

18. 10
CHAPTER 4
CONSTRUCTION OF FERRO-CEMENT
There are four phases of construction of ferro-cement:
1. Fabrication of skeleton frame system
2. Fixing of bars and mesh
3. Application of mortar and
4. Curing
The quality of mortar and its application is the most critical phase.
There are 4 methods to apply mortar:
A. Hand plastering
B. Semi mechanised process
C. By centrifuging
D. Guniting
There is no form work required in ferro cement construction in conventional reinforced concrete.
So, it is more suitable for structures as shells with curved surfaces and other free form shapes.
First the skeleton frame is made using small diameter steel rods bent to the required shape,
generally cylindrical in shape. Usually this frame provides rigidity to the whole structure before
plastering or impregnation. Placing of mortar is also known impregnation of mesh with the
matrix.
On both sides of the skeleton frame the required numbers of wire mesh layers are fixed. First
external mesh layers are fixed and tied to the frame bars. The mesh should be fixed by staggering
the hold positions to size. There should be left a space of 1 to 3 mm between two mesh layers. A
minimum overlap of 80 mm should be provided Whenever two pieces of the mesh are to be
joined, and tied at an interval of 80 to 100 mm centre to centre.

19. 11
4.1 Hand Plastering
It is the most critical operation in ferro cement casting. To give desired performance mortar
impregnation should be proper, the quality of the structure should be good.
A sufficient quantity of mortar should be dashed from outside through the layers against a G-1
sheet held on the other side. The mortar is dashed from the outside and the flexible G-1 sheet is
moved around. Till the whole structure is built up the process is continued. It should be ensured
that no voids are left in the body of the structure, during process of putting the mortar.
Figure 4.1 - Hand Plastering
It can be ensured by using a wooden hammer of 150 mm long wooden handle and about 100 mm
diameter. The mild hammer blows are given to the temporarily held form to remove the voids.
For compacting the mortar, it will give sufficient vibrations. The whole thickness is built up
gradually in two consecutive dashing of mortar and then both internal and external surfaces are
made smooth.
Boat hulls and shells like structures are built by the technique known as two operation mortar
impregnations. First the outside mesh is plastered and the inner layer is left exposed in this
system. The excess mortar is scrapped by wire brushes and trowel. Till it attains sufficient
strength the mortar is left for setting for carrying the load from the inside during the application
of a second layer of mortar. Fine cement slurry is sprayed over the entire inner surface before
applying the second layer.

20. 12
In structures where thickness is more than 20 mm, and many layers are used as reinforcement in
such cases it is desirable to do the casting in three layers. The middle or core layer is applied first
covering one layer of wire mesh and the skeleton steel. The core is cured at least for 3 days
before the other two layers of mortar are applied This core provides a firm surface for mortar
application on its top and bottom. For getting the good bond, between new and old mortar
cement slurry should be sprayed over the middle layer.
For thin cylindrical units of about 6 mm diameter,1 m diameter steel rod at a spacing of 15 cm be
used for making a cage of cylindrical shape and then woven or chicken mesh can be tied to the
mesh and impregnated or plastered., the use of chicken mesh is not advisable in such type of
construction as it is very flexible and plastering over it may not be satisfactory.
In this method the minimum thickness of the section works out to be more than 20 mm and the
control of thickness is difficult. By this method the greater thickness not only makes it
uneconomical, but also some technical advantages are lost. The strength obtained by hand
plastering or impregnation is lower compared to other methods due to poor compaction of mortar.
By this method the units cast may be used for pipes, storage structures and gas holder units etc.
This method of casting is suitable of units of shapes for which making of mould is difficult. This
method can also be applied for making cylindrical shaped units of size approximately 60 cm in
diameter or above.
4.2 Semi Mechanised Process
For making ferro cement cylindrical units a semi mechanised process has been developed by
Structural Engineering Research Centre (SERC) Roorkee. A central cylindrical mould is used in
this process. One layer of wire mesh is wound over this central mould. A 4 mm diameter wire is
tied at a spacing of 150 mm in both directions over this layer. One layer of chicken mesh is
wound over this wire layer. This forms the complete wire mesh system of reinforcement.

21. 13
Figure 4.2 - Semi Mechanised Process of Plastering
Now the cement sand mix prepared is plastered layer by or layer impregnated. The thickness of
the unit is reduced due to the tightly wound mesh around the form work, with this system, units
upto one cm thickness can be cast containing two layers of wire mesh in that thickness i.e.
Within 1 cm thickness. This system is called semi mechanised as the mould can be rotated to
facilitate dashing of mortar.
4.2.1 Advantage of Semi Mechanised Method
Following advantages have been observed of this method:
1. Better compaction can be obtained by means of a straight edge pressed against the inner
mould in this method.
2. In this method the uniformity of thickness is better than hand plastering.
3. The wire mesh can be wound tightly over the mould and also can be tightened during the
casting operation. This helps in looseness and avoiding unevenness of thickness in the mesh.
4. This system does not need any sophisticated equipment and electricity.

22. 14
5. Local, un-skilled people can handle this process.
6. This process can be easily adopted in rural areas.
7. The cylindrical units of size upto 1.0 m or above can be cast by this process.
Figure 4.3 - Guniting
4.3 Centrifuging Method
Generally centrifuging process is adopted for the fabrication of concrete cylindrical units. The
first crack strength of ferro cement has been observed higher in comparison of normal reinforced
concrete. Thus, the pipe thickness can be reduced, resulting in lesser dead weight. The mild steel
reinforcement cage has been replaced by wire mesh layers cage in the existing centrifuging
process. The trial casting at sercroorkee has shown that this method can be adopted for casting
ferro cement units. Due to good compaction as high-pressure pipes, ferro cement pipes cast by
centrifuging process can be used.

23. 15
4.4 Guniting
The process of guiniting can be adopted for applying the mortar to the wire mesh system. For
mass production of ferro cement prefabricated units this process seems to be suitable. An hour
will yield good results for a continuous process of layer guniting with an interval. If the process
is applied properly by an experienced gun man it can produce uniform and good compacted
surface.

24. 16
CHAPTER 5
PROPERTIES OF FERROCEMENT
5.1 Impact Resistance
Drop-impact tests on panels 53 indicate that the severity of cracking inflicted varies significantly
with the type of reinforcement, but the fundamental governing parameters are not established.
Tests using flow of water through the specimen after testing to assess the damage and ballistic
pendulums to produce the impact show that damage decreases as the strength and specific
surface of the mesh reinforcement increase. The impact strength of ferro cement has been found
to increase linearly with the increase of ultimate strength and specific surface (volume fraction)
of mesh reinforcement. Further the element having welded wire mesh reinforcement for the same
reinforcement fraction showed highest impact strength while chicken mesh reinforced section
showed lowest impact strength. The impact strength of woven mesh reinforced ferro cement is
found higher than chicken wire mesh and lower than welded wire mesh reinforced elements.
5.2 Crack Development and Leakage
In terms of average crack spacing and the average and maximum width of cracks crack
development is considered in this section. The average crack spacing decreases with increasing
specific surface for both tension and flexure for mesh-reinforcing systems. However, other
factors also influence crack development, the average crack spacing corresponds closely to the
transverse wire spacing, and the average crack width reduces as this spacing decrease. For the
same size meshes, crack widths are smaller for the welded type than for the woven variety.
5.3 Shrinkage and Creep
The shrinkage potential of the mortar matrix is governed largely by its water content, which in
turn is governed by the workability required for placement, the sand gradation, and the presence
of additives such as lime, pozzolan, air-entraining agents and water-reducing, etc. Thus, the use
of admixtures can reduce shrinkage of the matrix as circumstances permit the and selection of

25. 17
low-workability placement techniques such as shotcreting, the choice of a sand without
excessive fines.
5.4 Compressive Strength
By the properties of cement mortar matrix, the behaviour of thin ferro cement element under
compression primarily is controlled. Its compressive strength varies from 27.5 to 60 Mpa.
5.5 Tensile Strength
The tensile strength of ferro cement depends mainly on the tensile strength and the volume of
reinforcement in the direction of force of the mesh. The allowable tensile stress is taken as 10.0
Mpa and ultimate tensile strength is 34.5 Mpa.
The tensile behaviour may be divided into three groups:
1. Precracking stage.
2. Post cracking stage.
3. Post yielding stage.
A ferro cement member subjected to increasing tensile stresses behaves like a liner elastic
material till the development of first crack in the matrix. Once the cracks are developed, the
material enters the stage, of multiple cracking and this stage continues upto the point where wire
mesh starts to yield. Without any significant increase in the width of the crack in this stage
numbers of cracks go on increasing with the increase in tensile stress. The mortar enters the
stage of crack widening with the yield of reinforcement. At this stage the number of cracks
remains constant, but the width of crack goes on increasing. The behaviour is mainly controlled
by the reinforcement bars.
5.6 Fatigue Strength
The fatigue behaviour of ferro cement flexural elements is governed by the tensile fatigue
properties of pre-stressed concrete beams and mesh like reinforced. Under cyclic loading the
fatigue strength of ferro cement is poor.

26. 18
CHAPTER 6
ADVANTAGES AND DISADVANTAGES
6.1 Advantages
There are many advantages of construction of the ferro cement, which are given as following:
 The construction technique of ferro cement is simple. It does not require skilled labour.
 Complete or partial elimination of form work is possible.
 Ferro cement construction is easily amenable to repairs in case of local damage due to
abnormal loads as impact load.
 Raw materials required for Ferrocement construction are easily available
 The fabrication of the mesh can be done in many shapes that suits the requirements
 Ferrocements are more durable and are cheaper than steel and wood
 Application of Ferro-cement doesn’t require any heavy machinery
Advantages of ferro-cement
 High ductility
 High resistance to cracking width
 Ability to undergo large deflection
 Improved impact resistance and toughness
 Good fire resistance
 Good impermeability
 Low strength to weight ratio
 Low maintenance costs
6.2 Disadvantages
There are many disadvantages of use of ferro-cement, which are given below:

27. 19
 There is excessive shrinkage due to higher cement content. Constant curing is needed for
a period of 7 days to avoid any shrinkage cracks.
 Prone to corrosion of GI mesh rods MS and due to incomplete coverage of materials by
mortar
 Ferro-cement is labour intensive. So, where the labour costs are high, it might not be
economical to use ferrocements in places.
 As ferro-cement components are usually thin structures, another factor is Buckling that
needs to be taken into consideration during
 Number of labour will be higher.
 Rust can be developed on reinforcement if not covered properly by mortar.
 It is hard to do welding etc properly.
 Binding mesh and rod along can be time consuming.

28. 20
CHAPTER 7
APPLICATIONS OF FERROCEMENT
Due to the very high percentage of continuously running and well distributed steel reinforcement,
the ferro cement behaves like steel plates. Its ductility, cracking resistance, fatigue and impact
resistances are higher than that of normal concrete. The impermeability of ferro cement product
is far superior than ordinary R.C.C. products.
Due to its properties the ferro cement can be used for the following purposes:
 Ferro cement can be used for casting domestic overhead tanks. These tanks being flexible
and light can be transported and hoisted without difficulty. The out let and inlet
connections also can be done easily with the help of modem adhesives like “m seal”.
These tanks will be cheaper than any other type of material tanks.
Figure 6.1 - Ferro-Cement Tank
 In villages these tank units can also be modified into silos for storing grains. These tanks
will help in preserving grains from rodents and moisture effect.
 Similar ferro cement tanks can be used in villages as gas holding units in ‘Gobbar gas’
plants. With some modifications ferro cement tanks can also be used as septic tanks.
 Due to the favourable properties of ferro cement, this material has been used widely for
boat building in U.S. U.K. and New Zealand. It has been reported that 14 m long ferro

29. 21
cement boat weighs remains only 10% more than the wooden boats. Ferro-cement boats
are found 200% cheaper than steel boats, 35% cheaper than timber boats and 300%
cheaper than fibre reinforced concrete boats.
 The cost of ferro cement is only about 10% of the cost of cast iron. Thus, the use of ferro
cement manhole covers is becoming very popular, where it is not subjected to heavy
vehicular traffic.
Figure 6.2 - Ferro-Cement Boat
Figure 6.3 - Ferro-Cement Pressure Pipes

30. 22
 For pre-fabricated roof units ferro cement is becoming more popular material. The folded
plates of ferro cement being light can be advantageously used as prefabricated roof units.
A 3 cm thick ferro cement folded plate with two layers of chicken wire mesh can be used
safely over a 3.5 m span. It can also be used for prefabricated channel units for
construction of roof.
 Ferro cement being a light material, considerable reduction in self-weight of structure and
foundation cost can be reduced to a great extent. A 10% saving in roof cost, 15% saving
in steel consumption and 30% reduction in dead weight on supporting structure has been
observed in USSR by the use of ferro cement.
 For the production of pressure pipes ferro cement is found most suitable material. It is
much lighter than normal RCC pipes.
 Ferro cement also is found suitable for casting curved benches for gardens, parks, and
open cinema theatre. It can also be used to cast tree guards. They can be cast in two parts
to facilitate their removal at a later data.
Figure 6.4 - Ferro-Cement Bench

31. 23
CHAPTER 8
NEED TO STUDY
Scope of research needs the most desirable characteristics of ferrocement are related to the
subdivision and distribution of the reinforcement throughout the mortar. But at what point in the
subdivision is ferrocement just another form of reinforced concrete. There have been attempts to
set lower limits on the volume fraction or specific surface of reinforcement that would establish
the boundary between ferrocement and reinforced concrete. But such efforts could be misleading
because the characteristics of ferrocement are continuous function of the degree of subdivision
of the reinforcement. The issue becomes even more complex when one recognizes that the
reinforcement can take the form of reinforcing bars or strands used in combination with mesh of
relatively small diameter elements. Moreover, since the definition of an allowable service stress
can be related to an allowable crack width which depends on the degree of dispersion of the
reinforcement, the dilemma arises of having design stresses related to the manner in which the
reinforcement is dispersed. No doubt, allowable stresses will also be related to the type of
reinforcement (ductile or high strength) and the type of application (roof elements, tanks, wall
panels, etc.). The above discussion emphasizes the fact that the principal research which needs in
ferrocement will continue to be in the area of understanding the fundamental mechanism
whereby the matrix and reinforcement interact to distribute strains, improve first-crack strength,
spacing of cracks and control the size.
Specific research needs Although there is a very extensive range of possible research activities, a
few special areas will be mentioned. These relate to, fatigue strength impact resistance,
compressive strength, corrosion, with various types of meshes, and strength under multiaxial
loading conditions. Test data on in-plane shear strength is scant. The in-plane shear is important
when ferrocement is used as wall partitions or panels in structures subjected to “racking” or in-
plane shear forces due to wind and earthquake loads. Test data for combined load conditions
such as in-plane flexure and tension, shear and compression are needed. An example is the use of
ferrocement for folded plate roof elements in long span lightweight construction where in-plane
bending and shear stresses are important. In ferrocement construction, connections are

32. 24
sometimes unavoidable. So far, one study has reported tests on in-situ connections. Further
investigations are needed to study connections between precast elements to broaden the scope of
ferrocement application. Research on long term durability and behavior are limited. Tests on the
fire resistance of ferrocement are limited at present. to ferrocement, the cover requirements for
reinforced concrete to achieve minimum fire ratings cannot be applied. This often hinders it’s
use by engineers and architects who must, when appropriate, secure a related exemption from the
building official. Performance criteria for rectangular mesh must be developed for other types of
wire mesh reinforcement. The performance of ferrocement is greatly dependent on the
characteristics of the reinforcing mesh. There is a need to specify and determine an optimum
range of properties for the mesh, such as wire spacing, wire diameter, and the stress-strain
characteristics of the mesh system. New assemblies and mesh systems may be specifically
designed for ferrocement applications. It is very likely that new developments in the mesh
system will render ferrocement competitive in all applications where thin elements are used.
Durable and long-term effective sealants are needed for ferrocement, especially in marine
applications, to prevent penetration of water and salts that could lead to corrosion of the
reinforcing mesh.

33. 25
CHAPTER 9
CONCLUSION
Ferro-cement come into wide spread use only in the last two decades and still in its infancy. To
enable safe construction and design of many types of Ferro-cement structures sufficient design
information is available and adequate field experience has been acquired.
Whether it can economically compete with alternate materials depends on the location and type
of application. For industrially developed countries, Ferro-cement seems economical for medium
storage tank, roof shells, boat, tank and the ease of forming complicated shapes and lighter
weight of Ferro-cement can be safely exploited.

34. 26
REFERENCES
i
Vatwong Greepala, Pichai Nimityongskul, 2008,” Structural integrity of ferrocement panels
exposed to fire”, Cement & Concrete Composites 30 (2008) 419–430.
ii
Mohammad Taghi Kazem, Reza Morshed, 2005,” Seismic shear strengthening of R/C columns
with ferrocement jacket”, Cement & Concrete Composites 27 (2005) 834–842
iii
Nahro Radi Husein, V. C. Agarwal, Anupam Rawat, 2013,” An Experimental Study on Using
Lightweight Web Sandwich Panel as a Floor and a Wall”, International Journal of Innovative
Technology and Exploring Engineering (IJITEE) ISSN: 2278-3075, Volume-3.
iv
Ihsan Qasim Mohamad, 2012,” Analysis of Ferrocement Slabs Using Finite Element Method”,
Basrah Journal for Engineering Science.
v
D.R Seshu and A.K Rao,1998,” Behaviour of ferrocement confined reinforced concrete (FCRC)
under axial compression”, Materials and Structures, Vol. 31, pp 628-633.
vi
Shuxin wang, A. E. Naaman, Victor C. Li., 2004,:Bending Response of Hybrid Ferrocement
Plates with Meshes and Fibers”, Journal of ferrocement, vol.34, No.1
vii
V.M. Shinde, J. P. Bhusari,” Response of Ferrocement Confinement on Behavior Of Concrete
Short Column”, IOSR Journal of Mechanical and Civil Engineering (IOSR-JMCE), ISSN: 2278-
1684, PP: 24-27.
viii
S.M. Mourad, M.J. Shannag,” Repair and strengthening of reinforced concrete square
columns using ferrocement jackets”, Cement & Concrete Composites vol.34, pp288-294.
ix
Shouping SHANG, Fangyuan ZHOU, Wei LIU,2009, Calculation of diagonal section and
cross-section bending capacity for strengthening RC structure using high performance
ferrocement laminate”, Front. Archit. Civ. Eng. China, 3(3): 330–338
x
Letitia NADASAN, Traian ONET, 2013,” Durability of Ferrocement”, International Journal of
Engineering.
xi
Prem Pal Bansal, Maneek Kumar, S.K.Kaushik,” Effect of Wire Mesh Orientation On Strength
Of Beams Retrofitted Using Ferrocement Jackets”,Vol.2,Issue1.
xii
A. A. Skudra and A. M. Skudra,1997” ELASTIC CHARACTERISTICS OF
FERROCEMENT REINFORCED BY HEXAGONAL GRIDS”, Mechanics of Compos#e
Materials. Vol. 33, No. 2

35. 27
xiii
Mohammad Ashraf , Akhtar Naeem Khan, Qaisar Ali, Khan Shahzada
xiv
Amjad Naseer,” Experimental Behavior of Full Scale URM Building Retrofitted with
Ferrocement Overlay”, Advanced Materials Research Vols. 255-260 (2011) pp 319-323
xv
Shuxin Wang, A, E, Naaman, Victor C. Li, 2004, “ Bending response of hybrid ferrocement
plates with meshes and fibers”, Journal of Ferrocement, Vol. 34, No.1.
xvi
Mahmoud Abo El-Wafa, Kimio Fukuzawa,2010,” Flexural Behavior of Lightweight
Ferrocement Sandwich Composite Beams”, Journal of Science & Technology Vol. (15) No.(1).
xvii
Vatwong Greepala and Pichai Nimityongskul,2007,” Influence of Heating Envelope on Post-
Fire Mechanical Properties of FerrocemenJt ackets”, Thammasat Int. J. Sc. Tech., Vol. 12, No. 3.
xviii
Letita Nadasan and Traian onet,2013,” POSSIBLE USE OF FERROCEMENT IN
ROMANIA”,