动态多步流动法预测非饱和土水力学参数  

Prediction of unsaturated soil hydraulic parameters by dynamic multistep outflow method

作　　者：何锦堂[1,2] 颜荣涛 程允[1] 赵续月 梁维云 陈永健 肖锋[3] HE Jin-tang;YAN Rong-tao;CHENG Yun;ZHAO Xu-yue;LIANG Wei-yun;CHEN Yong-jian;XIAO Feng(Guangxi Key Laboratory of Geomechanics and Geotechnical Engineering,Guilin University of Technology,Guilin 541004,China;Zhongtian Construction Group Co.,Ltd.,Dongyang 322100,China;Suizhou Branch of State Grid Hubei Electric Power Co.,Ltd.,Suizhou 441300,China)

机构地区：[1]桂林理工大学广西岩土力学与工程重点实验室,广西桂林541004 [2]中天建设集团有限公司,浙江东阳322100 [3]国网湖北省电力有限公司随州供电公司,湖北随州441300

出　　处：《桂林理工大学学报》2018年第3期488-493,共6页Journal of Guilin University of Technology

摘　　要：选取4种具有代表性的土样,运用Wei和Muraleetharan提出的饱和度随时间的演化方程对其进行动态多步流动试验,来预测其非饱和土的水力学参数。以平衡态法的试验结果作为参考标准,将预测结果与其相比较发现:在砂土与粉土的试验中,试样饱和度较大时两者偏差较大,这是由于试验采取的3 Bar陶土板的渗透系数与砂土和粉土的渗透系数相差较大,导致孔隙水不能被及时排出。粉质黏土的预测结果与平衡态试验结果非常接近,说明该方法对粉质黏土的预测非常有效。由于受到实验设备与陶土板规格的限制,黏土的预测范围偏小,但是预测结果较为理想。通过平衡态实验发现,4种土样的土水特征曲线均为典型的"S"型曲线,以进气值与残余饱和度为分界点可将其分为三部分。动态多步流动试验根据该三个部分来确定试验的吸力增量与吸力步长,并给出了合理的值。Four kinds of typical soil samples were used to predict the unsaturated soil hydraulic parameters by the dynamic multistep outflow experiments with the time evolution equation by Wei and Muraleetharan.The results of the equilibrium method were used as the reference standard,and compared with those of the predicted results.It is found that when the sample saturation is great,there are more differences between them in the tests of sandy soil and silty soil.This is because the permeability coefficient of 3bar clay plate is totally different from that of sandy soil and silty soil,which leads to the fact that pore water can not be discharged in time.The prediction of silty clay soil is very close to the equilibrium test results,which shows that this method is very effective for predicting silty clay soil.Due to the limitation of the specifications of the experimental equipment and the clay plate,the prediction range of clay is small,but the prediction results are satisfactory.It is found that the soil water characteristic curves of the four kinds of soil samples are typical“S”curve by the equilibrium tests,which can be divided into three parts by the air entry value and the residual saturation.According to the three parts,the dynamic multistep outflow experiments can be used to determine the value of suction increment and suction step.

关 键 词：动态多步流动法 水力学参数 土水特征曲线 渗透系数 

分 类 号：TU41[建筑科学—岩土工程]