An improved Mesri creep model for unsaturated weak intercalated soils

ZHU Yan-bo(祝艳波)^{1, 2}, YU Hong-ming(余宏明)¹

(1. Faculty of Engineering, China University of Geosciences, Wuhan 430074, China;
2. College of Geology Engineering and Geomatics, Chang’an University, Xi’an 710054, China)

Abstract:The weak intercalated soils in redbed soft rocks of Badong formation have obvious creep characters. In order to predict the unsaturated creep behaviors of weak intercalated soils, an unsaturated creep model was established based on the unsaturated creep tests of weak intercalated soils by using GDS triaxial apparatus. The results show that the creep behaviors of intercalated soils are apparent and significantly affected by matric suction. Based on this, an empirical Mesri creep model for intercalated soils under varying matric suctions was built. The fitting results show that the parameters E_d and m of this model are in good power relations with matric suction s and stress level D_r, respectively. An improved Mesri creep model was established involving stress-matric suction-strain-time, which is more precise than the Mesri creep model in predicting the unsaturated creep behaviors of weak intercalated soils.

Key words:unsaturated soils; creep; matric suction; improved Mesri model