An experimental technique for the K0, the coefficient of earth pressure at rest, is presented. The technique consists of drained vertical compression of a triaxial specimen using the strain path control, in which a positive control of the strain increments rather than the conventional stress increments is exercised. The method does not require the use of any lateral strain sensors as used in previous studies and is free from any side friction affects, typical of oedometer testing. A detailed series of tests on three (3) sands are presented to illustrate the capabilities of the proposed technique. Possible influence of stress/strain history the soil inevitably experiences during sampling or reconstitution together with the initial state of stress prior to initiating zero lateral strain loading on the measured K0 are critically reviewed and evaluated. It is shown that the requirement of absolute zero lateral strain may not be essential for obtaining credible estimates of K0 as long as the ratio of radial to axial strain during vertical compression does not exceed about 3 to 5 %.
IOS Press, Inc.
6751 Tepper Drive
Clifton, VA 20124
Tel.: +1 703 830 6300
Fax: +1 703 830 2300 firstname.lastname@example.org
(Corporate matters and books only) IOS Press c/o Accucoms US, Inc.
For North America Sales and Customer Service
West Point Commons
Lansdale PA 19446
Tel.: +1 866 855 8967
Fax: +1 215 660 5042 email@example.com