ESTIMATION OF COEFFICIENT OF EARTH PRESSURE AT REST USING MODIFIED OEDOMETER TEST

摘要

A series of experimental trial for estimating the coefficient of earth pressure at rest, K_0, is presented. The developed apparatus is a modified Oedometer covered with pressurized chamber specially designed for K_0 determination based on the principle of effective stress originally proposed by Ohta et al. (1979). K_0 is estimated from the developed apparatus primarily by means of load cell and auxiliary by means of pore pressure transducer aiming at confirming the test results. K_0 triaxial consolidation is carried out to verify the result of purposed method. K_0 values are obtained using Oedometer tests on two samples one of which is taken horizontally and the other is taken vertically from a block sample and K_0 values from empirical equation are also estimated for comparison. It was found that the proposed method gives a comparable K_0 of kaolin to K_0 triaxial consolidation method but somewhat higher than those from empirical equations and lower than K_0 obtained using Oedometer.