Remarks on consolidation in unsaturated soils from experimental results

This paper presents the experimental results from several conventional oedometer tests conducted on compacted and unsaturated soils. Soil samples of medium plasticity, but with different grain size distribution and degree of saturation were tested. Some of these tests were interrupted before consolidation was achieved, and the water content of the soil was measured both before and after each test. The results point out that the recorded time-settlement curves consist of two distinct stages that are characterized by a different settlement rate. The early stage should essentially be ascribed to the faster dissipation of air pressure, while the final stage should be caused by the gradual expulsion of water from the soil. The results are also analysed using Terzaghi's theory [1] in order to ascertain whether this theory is suited to simulating the time-histories of settlement recorded during the tests.