where, ( , ) and ( , ) are the volume and the pressure at the point A and B respectively and = volume of measuring cell in its natural state (535 ml).

The value of depends on the size of the borehole. The injected volume at the limit pressure is thus:

= + + = 2 + where, = volume required to inflate pressuremeter and push soil to its original position; and = initial volume of the measuring cell. The allowable bearing capacity of clayey soils for shallow and deep foundations is generally determined from the pressure test results by the empirical and semi-empirical methods. For shallow foundations, the allowable bearing capacity may be considered as,

for deep foundations, the allowable fractional resistance may be taken as

.

Thus, the pressuremeter gives in-situ lateral stresses in the ground, the stress strain behavior and the strength of the soil at different depths. The test takes only 10-15 minutes after drilling operation. Since the results are available within a short time it is possible to arrive at quick conclusions regarding the suitability of the site to be adopted.