Experimental study on the hydro-mechanical behavior of Boom clay

In the context of research into deep nuclear waste disposal, Boom clay,a stiff soil from theUnderground Research Laboratory in Mol, Belgium, has been studied in various works. In this paper, containing X-ray diffractiontests, oedometertests, consolidated undrained shearing (CUS) tests and scanning electron microscopic (SEM) tests, a series of experimental studies intended to study the hydro-mechanical behavior and microfabric of Boom clay are presented. X-ray diffractiontests and SEMtests further highlight the high content of clay mineral of Boom clay(about 60% inaverage). Preconsolidation pressure, which is about 5.0MPa, was determined by oedomete rtests. High swelling property under hydro-mechanical coupling effect has been investigated on the clay samples during the CUS test, and also high viscous potential has been represented under shearingrate of 20 mm/min. SEM tests show that the microstructure of Boom clay arranged more directional and denser, and it can be observed clearly through the microstructure variation of pores and fissures.