Grillage Foundation design is mostly suitable for heavy structural loads from columns, piers or beams which are essential to transmit bearing capacity of a soil relatively inferior.
The grillage foundation can easily disperse the load over a broad area of the subsoil. This foundation facilitates to resist deep excavations because the required base area is arranged for the load of the transmission. The foundation depth is restricted from 1m to 1.5m.
The grillage foundation contains two or more tiers of beams placed at proper angles to disperse the load over a extensive area.
Usually, this type of foundation is undertaken toward heavy structure columns piers and stanchions. Grillage is made with steel I I section (R.S.J) placed in single or double large.
The second larger – The number of R.S.J.S and they’re spaced separately based on load of the structure and the bearing capability of the soil.
Ground Improvement with inclusion of Load or enhancing operative stress
When load is delivered on the ground, it is compressed. The range and required time may vary according to the placing of ground particles, on the degree of saturation as well as smooth draining of the soil. If load is delivered for loose and specifically unsaturated fills, it can cause quick settlement.
In order to build a grillage foundation, a trench of the essential width and depth is excavated. The trench surface is leveled and rammed. Above the rammed surface, a cement concrete layer is applied. It should be condensed properly to transform it water-resistant. R.S.J.S contain necessary dimension that are place at consistent gaps. For implanting the lower flanges of the R.S.J.S into the concrete, rich cement mortar is poured. The pipes and bolts are used to attach the R.S.J.S collectively. The bolts are pushed into web of the R.S.J.S.
G.I. pipe pieces are arranged among R.S.J.S, and a long bolt is passed over all the holes and pipes. This will attach the R.S.J.S collectively and develop a solid mass.
Grillage Foundation Types
1. Steel Grillage Foundation
Steel Grillage Foundation is developed with steel beams and it is structurally called rolled steel joists (RSJ), applied in two or more tiers.
2. Timber Grillage Foundation
Timber grillage is undertaken for heavy load wood column or masonry wall. Benefits of Grillage Foundations.
Steel grillage foundation is more useful for contractors as compared to wooden grillage.
Installation Speed – Contractors can make significant savings in time through a grillage foundation.
Suitability – Grillage foundations are mostly used in place of poured concrete and huge time is saved because of smooth installation process.
Costs Reduction – Contractor can obtain discount in cost as there is least possibility for disarrangement of transport infrastructure.
Multipurpose foundation solution – The technology supports various applications.