类软土单轴剪切蠕变特性研究

Study on Uniaxial Shear Creep Properties of Quasi-soft Soil

类软土是指炭质页岩、炭质灰岩、炭质泥岩等含炭的一套软质岩和其风化物,在特殊的工程地质条件和气象水文条件下形成的饱水层,受长期浸泡软化或间有微生物作用形成的坡残积、坡崩积和坡洪积软土。类软土具有的蠕变特性,导致滑坡产生连续滑动。研究类软土的蠕变规律,可为滑坡的建模及稳定数值计算奠定力学基础。通过类软土的单剪蠕变试验,得到了类软土剪应力—应变—时间关系的蠕变曲线;选择Burgers粘弹性本构模型描述类软土的流变性状,确定了类软土的剪切流变参数;通过对剪应力—应变曲线分析,得到了类软土的长期强度值。

Quasi- soft soil is one of the special eluvial- declivous, colluvlal -clecllvous and diluvialdeclivous soft soils that a suit of carbonaceous soft rocks, such as carbonaceous shale, carbonaceous lime-stone, carbonaceous mudstone, and weathering matter are transformed in the situations of the special engineering geological conditions, meteorologic and hydrologic conditions, saturated and microbial conditions. It is very important for landslide how to describe the creep behavior of quasi - soft soil. The relationship between shear stress, strain and time is presented on basis of simple -shear creep test, the creep behaviors of quasi - soft soil are described by the Burgers visco - elastic model. From the test results, the shear rheological parameters and longterm strength are obtained.