Controlled Gradient Consolidation Test

A new consolidation test based upon maintaining a constant pattern of hydrostatic excess pressure in the test specimen is described. New apparatus and testing technique are developed for the test. The controlled gradient test can be performed at a slow rate strain that is practically constant for a particular test. The rate of strain can be selected from a fivefold range, permitting study of the effect of strain rate on the consolidation characteristics. These strain rates are still faster than the rates occurring in the field, but are closer to the field rates than the rates in the conventional test. In the new test the coefficient of consolidation is computed using a simple formula instead of by curve fitting schemes. Results of the new test are compared with those of the conventional test.