结构损伤对膨胀土屈服特性的影响

 利用与CT机配套的非饱和多功能土工三轴仪，对干湿循环不同次数的膨胀土进行控制吸力为常数的各向等压试验，从细观上研究损伤对膨胀土屈服应力的影响。研究表明：屈服应力随着结构损伤的增大而减小；屈服前压缩指数随着结构损伤的增大而增大。根据细观试验数据，分别提出结构参数与屈服应力和宏观变量之间的定量表达式，进而将Barcelona膨胀土模型推广到结构损伤情况。

INFLUENCE OF STRUCTURAL DAMAGE ON YIELDING CHARACTERISTICS OF EXPANSIVE SOILS

By using CT-triaxial apparatus for unsaturated soils，compression tests under confined suction are carried out with remolded expansive soils which are suffered from multi-drying-wetting cycles. The yielding characteristics of expansive soils influenced by structural damage are researched from the viewpoint of meso-scale. The results indicate that，yielding stress would drop off gradually while the level of structural damage increases. Compression index before yielding stress appearing would increase slowly while damage level would increase gradually. Based on the test data，the quantitative equations of structural parameters along with yielding stress and macrovariable are employed for the Barcelona expansive model with structural damage.