A macro-structural constitutive model for partially saturated expansive soils

论文类型：

期刊论文

第一作者：

Li, Wugang

通讯作者：

Yang, Q (reprint author), Dalian Univ Technol, Inst Geotech Engn, Dalian 116024, Peoples R China.

合写作者：

Yang, Qing

发表时间：

2017-08-01

发表刊物：

BULLETIN OF ENGINEERING GEOLOGY AND THE ENVIRONMENT

收录刊物：

EI、SCIE、Scopus

文献类型：

J

卷号：

76

期号：

3

页面范围：

1075-1084

ISSN号：

1435-9529

关键字：

Unsaturated expansive soils; Constitutive model; Suction; Swelling behaviour; Microstructure; Macrostructure

摘要：

The mechanical behaviour of unsaturated expansive soils is an important factor in the design of barriers for nuclear waste disposal. Double structural constitutive models for expansive soil have been developed based on the distinction between micro-structure and macro-structure of the expansive soil. Nevertheless, the micro-parameters and the coupling function of these models are hard to determine. To eliminate the limitations of these models, the concept of a macro-structural neutral loading line was introduced by adopting a simple assumption concerning the plastic swelling potential of unsaturated expansive soil. A macro-structural volume change equation of unsaturated expansive soil was derived using a macro-structural neutral loading line. The model was based on an existing model for non-expansive unsaturated soils. Only one new macro-parameter was introduced into the constitutive model compared to the original model. Finally, a comparison between predicted results and experimental data indicates that the proposed model has a remarkable ability to reproduce the mechanical and hydraulic responses of unsaturated expansive soils.