软岩堆石料降雨湿化变形试验研究

Experimental study on rainfall wetting deformation of soft rockfill materials

软岩堆石料受外部降雨引起的填筑体湿化变形显著,对工程变形控制和运行安全带来挑战。本文分析了降雨条件下材料湿化应变基本规律,发现早期降雨湿化应变占比较高,且与时间的关系可用双曲线较好描述;探讨了单次降雨材料湿化应变发展规律,发现前期单次降雨时湿化应变随时间的变化也具有双曲线特点;同时分析了降雨强度对整体湿化应变规律的影响,结果表明随降雨强度增大,材料湿化应变速率增加,但应变量值却有一定程度的下降。此外,也研究了降雨强度对单次降雨湿化应变的影响,建立了基于降雨条件的非饱和入渗双曲线湿化变形计算模型,基本能反映降雨导致的软岩堆石料湿化变形规律。

Wetting deformation of soft rockfill materials caused by external rainfall events is significant and often brings about challenges to engineering deformation control and operation safety.This paper presents an analysis of the basic law of material wetting strain under rainfall conditions,and reveals that the wetting strain caused by early rainfall accounts for a relatively big proportion and its time variation is well described using hyperbolic curves;For the case of a single rainfall event,we examine strain development during rainfall and demonstrate that its time variation in the early stage is also hyperbolic;Analysis on the influence of rainfall intensity on the overall wetting process shows that as rainfall intensifies,the rate of change in the strain increases but its magnitude decreases to a certain extent.To understand the variation in wetting strain with rainfall intensity in this case,we develop a model for calculating unsaturated infiltration wetting deformation in rainfall conditions based on the hyperbolic curve,and verify its applicability to prediction of the rainfall wetting deformation laws of soft rockfill materials.