|
Abstract The sedimentary soft rock is a kind of geomaterial that exhibits the mechanical properties of strain softening，rheology，and influenced by the intermediate principal stress. In order to describe these properties as comprehensively as possible，a new visco-elastoplastic constitutive model is developed. Based on the tij concept and subloading surface，this model uses a state variable r which is a void ratio difference between the over- consolidated and normal consolidated states，and introduces a non-homogenous function as an evolution law for r. Compared to the Cam-clay model，only 4 new parameters are added to the new model，which have explicit physical meanings and can be determined from triaxial tests. A progressive failure of soft rock slope due to heavy rain is taken as background，and soil-water coupled FEM is conducted to investigate the influences of 2 kinds of groundwater table changes on the failure. The shear strain，displacement vector and propagation of the failure among the slope are analyzed carefully to clarify its failure.
|
|
Received: 25 February 2010
|
|
|
|
