What Is Guniting?
Guniting is a process in which inferior or damaged concrete works can be effectively repaired. It is also used for providing an impervious layer.
Gunite is a mixture of cement and sand in usual proportion of 1:3. A special equipment known as cement gun is used to deposit this mixture on the concrete surface under a pressure of about 2 to 3 kg/cm2.
The surface to be treated is cleaned and washed. The nozzle of the gun is generally kept at a distance of about 80 cm from the surface to be treated. The velocity of flow through the nozzle is from 120 t0 160 m/sec.
Advantages Of Guniting:
1. High impermeability can be achieved.
2. The repairs can be carried out in any situation in very short time.
3. High compressive strength, say of the order of 500 to 700 kg/cm2 at 28 days can be obtained.
Disadvantages Of Guniting:
1 Production cost is very high.
2 Concrete can be wasted in excess amount.
1. Thin overhead vertical or horizontal surfaces.
2. Curved or folded structures such as tunnels, canals, reservoirs, swimming pools, pre-stressed tanks.
3. Stabilized rock slopes.
4. Restoration and repairing of old building and fire-damaged structure.
5. Waterproofing walls etc.