EFFECT OF OVERBURDEN PRESSURE ON MINI SPT VALUES

Abstract

The effect of overburden pressure on Mini SPT has been studied by carrying out exhaustive laboratory tests at different relative densities and different overburden pressures. The inten-sity of overburden pressure used in the present study was 0.40.2 kg/cm2 due to the salfweighi of the soil and 0.2-2.2 kg/cm2 due to the jacks and selfweight of soil of thickness 50 cm. The original relative densities were taken as 7.62, 45.25, 70.19 and 77.15 percent. Curves and equations have been. developed to apply the correction due to overburden pressure to Mini SPT values. A. correlation between Mini SPT values, relative density and over-burden pressure has been found. Till now (1985) the penetration value of the Mini al has been indirectly related to the soil properties_ through the penetration value—of SPT .A direct correlation between Mini SPT values and some of the important properties of soil such as relative density, angle of internal friction has been established