Annamacharya Institute Of Technology AndSciences

Ferro-cementPresented by

D. Manasa 13701A0129

Contents• Introduction• What Is Ferro-cement?• Materials Used In Ferro-cement• Properties Of Ferro-cement• Behaviour Of Ferro-cement• Process Of Ferro-cement• Cost Effectiveness Of Ferro-cement• Applications• Advantages• Disadvantages• Conclusion

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Definition

Ferro cement is a form of reinforcedconcrete using closely spaced multiplelayers of mesh and/or small diameter rodscompletely infiltrated with, or encapsulated

inmotor

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Typical Cross Section Of Ferro cement

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Materials Used In Ferro Cement

• Cement mortar mix

• Skeleton steel

• Steel mesh reinforcement or Fibre-reinforced

polymeric meshes

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Cement Mortar Mix

• OPC and fine aggregate

matrix is used

• sand occupies 60 to 75%

of the volume of the

mortar

• Plasticizers and other

admixtures are used

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Skeleton Steel

• Used to impart structural strength in case of boats, barges etc.

• Reinforcement should be free from dust, rust & other impurities

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Steel Mesh Reinforcement

• Available as woven/interlocking mesh and welded mesh

• Expanded-metal lath is also used

• Made from carbon, glass etc.

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Commonly used reinforcing mesh

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Chemical Admixtures in Ferro cement

• water reduction, with strength

and reduces permeability.

• Air entrainment, which increases

resistance to freezing and thawing;

• suppression of reaction between

galvanized reinforcement and

cement .

Water

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• Water should be portable.

• clean, and free from organic matter - silt, oil, sugar, chloride and acidic material

• pH equal or greater than 7 .

Mix Proportions

•Sand: cement ratio (by mass) 1.5 to 2.5

•Water: cement ratio (by mass) 0.35 to 0.60

Properties Of Ferro Cement

• It is a very durable, cheap and versatile material.

• Low w/c ratio produces an impermeable structures

• less shrinkage, and low weight.

• high tensile strength and stiffness

• better impact and punching shear resistance

• undergo large deformations before cracking or high

deflections

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Behavior of Ferro-cement in tension

RC in tension Ferro cement in tension

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Process Of Ferro-cement Construction

• Fabricating the skeletal framing system

• Applying rods and meshes

• Plastering

• Curing

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Cost Effectiveness

• Depends on type economic system and

applications.

• Relative cost of labor.

• Doesn’t need heavy plant or machinery.

• Low cost construction materials are used.

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Applications

• Floors And Roofs

• Waterproofing

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• Rural Applications

• Marine Applications

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• Transport System

• Agriculture Structures

• Fire resistant structures

• Soil stabilization

• Man hole covers

• Wall cupboards

• pipes

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Advantages Of Ferro -Cement:

• 20% savings on materials and cost• Suitability for pre-casting• Flexibility in cutting, drilling and jointing• Very appropriate for developing countries, labor

intensive• Good impermeability• Fabricated into any desired shape.• Ease of construction, low weight and long

lifetime.• Better resistance against earthquake.

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Disadvantages of Ferro-Cement:

• Corrosion of the reinforcing materials due to theincomplete coverage of metal by mortar.

• It is difficult to fasten to Ferro-cement with bolts, screws,welding and nail etc.

• Large no of labors required.

• Cost of semi-skilled and unskilled labors is high.

• Tying rods and mesh together is especially tedious andtime consuming.

• Low ductility

• Susceptibility to stress rupture failure

• It can be punctured by collision with pointed objects.

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Conclusion

In India, Ferro-cement is used often because theconstructions made from it are more resistant toearthquakes. It has a wide range of other usesincluding sculpture and prefabricated buildingcomponents.

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