饱和砂性土非线性蠕变模型试验研究

Study on nonlinear creep model for saturated sand

采用单向压缩试验研究了常州不同含水层饱和砂性土的蠕变特性。试验结果表明,饱和砂性土的变形既与应力有关,也与时间有关。在一定应力作用下,其变形随时间的增加而增加,经过一段时间后才能达到稳定,应变与应力、时间都呈非线性关系。对试验结果的统计分析表明:用幂函数可以很好地拟合饱和砂性土的应力-应变-时间关系。这一结论有助于更深入地研究长期抽水作用下的地面沉降问题。

The creep behavior of saturated sands is studied by uniaxial compression tests. The samples were taken from the aquifers of Changzhou in Jiangsu Province. Based on the test results, the relationship of stress-strain-time for saturated sands is obtained; and it could be expressed as power functions. The test results show that the strains for sands depend not only on the stresses exerted on them but also the time elapsed. That is to say that the sands have characteristics of nonlinear creep. The conclusion is very helpful to study the land subsidence due to extracting groundwater.