What is Ferrocement ?
Ferrocement is a composite material comprising rich cement which is highly reinforced with continuous and small diameter steel rods and wires. It may be defined as a sophistically designed well proportioned cement based compound in which optimum quantity of suitably sized steel sections are evenly dispersed for achieving remarkable homogeneity, ideal monolithic properties, excellent strength and absolute impermeability. Its engineering properties, not only in compression but also in tension, bending and fatigue are far superior.
Unlike RCC, its panels are quite thin. Its thickness is generally between 10mm to 40mm. It is light in weight and can be constructed to any shape of cross section. Hence, widely suited for Precast products.
Ferrocement construction is a high precision work. As the structure is normally around 25mm thick, there lies no scope for error in workmanship.
The construction process can be divided into 4 distinct phases:
1. Designing the structure: The basic steel structure has to be properly designed. Precision of design may make or mar the final outcome.
2. Fixing the steel frame: The correct quantity of steel has to be arrived at based on the use of the structure. Steel structure has to be properly fixed and then wrapped with adequate layers of chicken wire.
3. Mortar application: Cement - Sand mortar of correct ratio has to be applied on both sides of the structure. This is a very meticulous job. The application has to be good enough so that the finishing is smooth.
4. Curing: Recommended Curing is for 14 days.
Ferrocement is a low weight building system with high structural strength. It has lower maintenance costs over its lifetime and is more durable than its traditional counterparts. However, skill of the designer as well as the applicator is of paramount importance, as this is a high precision building system with zero margin of error.
In Ferro-cement while mortar provides the mass, the steel and wire mesh imparts tensile strength and ductility to the material. In terms of structural behavior it exhibits very high tensile strength-to-weight ratio and superior crack resistant performance. The distribution of small diameter wires over the entire surfaces enveloped with chicken mesh, provides very high resistance against cracking. Moreover many other engineering properties, such as toughness, fatigue resistance, impermeability are considerably improved.
Ferrocement construction eliminates/minimises use of formwork resulting in reduced construction costs. It also reduces maintenance cost as damages (if any) are localised and easily repairable.
- Immense Structural Strength : Due to perfect homogeneity and monolithic body
- Light Weight : Being thin and much lighter than RCC, hence portable and easy to handle and erect.
- Completely waterproof : No leakage or sippage. Even there is no sweating or dampness. So ideal for water retaining and moisture proof structures.
- Endearing Insulation : Very less conductive than steel and RCC. Hence cool in summer, warm in winter. Minimum condensation.
- Long durability : goes on gaining strength especially in contact with water/ moisture. Almost permanent life.
- Joint less structure : Being single bodied monolithic construction, there are no joints. Hence no chance of opening out.
- Excellent fire and explosion resistance : Almost complete fire resistant. Even temperatures up to 170 degrees C have not shown any effect.
- Zero maintenance : No recurring expense or botheration. Construct-Erect-Forget!!
- Easy reparability : Damage, if any, are always localized. Hence can be repaired quickly and easily.
- Mould ability to any shape : During construction it can be molded to any decorative shape. Hence tailor made attractive designs possible.
- Resistance to environmental deterioration : Almost immune to biological growths and atmospheric effects.
- Good vibration and sound absorbance
- Easily painted for decoration.
- Environment friendly construction : Construction blends with the environment, ambience & surrounding.
- Green Construction : uses locally available resources, green material and is labor intensive.
Ferrocement applications are free-form and can be limited only by one’s imagination. It provides easy mould ability and can take any form. It can be used for manufacturing precast building components that can be easily transported. Some popular uses are for making Septic Tanks, Water Tanks and Designer Roofing systems. Other specialized applications include silos, bins, boats, biogas holders, milk kiosks etc.