Interaction of Physico-Chemical and Geomicrobial Processes in Clay-Sulfate Rocks and Soils – Constitutive Model in Clay Rocks and Soils –

Research Project , Research Report 2001

Jiro YAMATOMI Dept. of Geosystem Engineering, the University of Tokyo
Hiroyuki TOSAKA Dept. of Geosystem Engineering, the University of Tokyo
Gento MOGI Dept. of Geosystem Engineering, the University of Tokyo
Tomochika TOKUNAGA Dept. of Geosystem Engineering, the University of Tokyo
Sangtae KIM Dept. of Geosystem Engineering, the University of Tokyo(Research Partners)
P. Amman Institute of Geotechnical Engineering, ETH
R. Nuesch Dept. of Materials, Institute of Polymers, ETH-Zentrum
A.J. Tien Dept. of Microbiology, ETH
H.H.Einstein Dept. of Microbiology, ETH
J.T. Germaine Dept. of Civil and Env. Eng., MIT

Abstract

Constitutive relationships, which can relate stress variables (net stress and suction) to state variables (void ratio and water content ratio) in swelling clay, are investigated in the present study. Additionally, the method to identify the tangent and nonlinearly elastic moduli of swelling clay is given, in which transversely isotropic behavior of hydromechanical coupling is incorporated based on the experimental results obtained by free swelling tests. Moreover, constant load swelling tests in uniaxial strain condition have been conducted and we find that swelling behaviors such as changes of void ratio, water content ratio, and saturation depend on stress level and/or constrained conditions and suction.

Keywords:

swelling behaviors, constitutive relations, hydromechanical coupling, transversely iso-tropic swelling, swelling test