复杂初始和边界条件对一维非饱和土固结的影响  

Influence of initial and boundary conditions on one-dimensional consolidation of unsaturated soil

作　　者：周万欢[1] 赵林爽 

机构地区：[1]澳门大学土木及环境工程系

出　　处：《岩土工程学报》2013年第S1期305-311,共7页Chinese Journal of Geotechnical Engineering

基　　金：澳门大学研究委员会资助项目MYRG189(Y3-L3)-FST11-ZWH;MYRG067(Y2-L2)-FST12-ZWH

摘　　要：基于Fredlund等提出的非饱和土一维固结理论,采用差分求积法分析了复杂的初始孔隙气压及水压分布,不同的边界条件对非饱和土固结的影响。通过一个简单初始和边界条件下的特殊算例与文献中已取得的结果进行比较,验证了该结果的正确性。作者采用的计算方法可以有效避免解析解中复杂的数学推导,而且相对于解析解仅限于特殊的初始和边界条件,这种分析方法适用性更加广泛。通过在算例中考虑不同的边界和初始条件,发现不同的初始孔隙压力分布和不同的边界条件在非饱和土的固结过程中有很大的影响。Unsaturated soil is common in practical geotechnical engineering and is defined by more characteristics than saturated soil.Based on the Fredlund and Rahardjo’s one-dimensional(1-D) consolidation theories of unsaturated soil,the behaviors of unsaturated soil under different initial and boundary conditions are investigated.The differential quadrature method(DQM) is employed to obtain the solutions that consider different boundary conditions and various initial pore water and air distributions.DQM is an efficient numerical technique for initial and/or boundary problems,and it can obtain sufficient accuracy with a small number of discretized points.It can avoid cumbersome computations in solving eigen-equations encountered with the analytical solution.A special case for which the analytical solution is available in the literature is employed to compare with and verify the accuracy of the DQM solution.Good agreements are found in the comparisons.Then the average degree of consolidation is studied for the different boundary conditions.Finally,the characteristics of the 1-D consolidation of unsaturated soil are investigated under various initial pore pressure distributions.It is found that the initial and boundary conditions have a significant influence on the consolidation of unsaturated soil.

关 键 词：非饱和土 差分积分法(DQM) 初始条件 边界条件 

分 类 号：TU43[建筑科学—岩土工程]