均布荷载下软土地基一维非线性固结的有限差分法  

Finite difference method for one-dimensional nonlinear consolidation of soft ground under uniform loads

作　　者：赵明华[1] 贺成斌[1,2] 马缤辉[2] 陈秋南[2] 雷勇[2] 

机构地区：[1]湖南大学土木工程学院,湖南长沙410082 [2]湖南科技大学土木工程学院,湖南湘潭411201

出　　处：《水利水电科技进展》2016年第3期26-30,35,共6页Advances in Science and Technology of Water Resources

基　　金：国家自然科学基金(51308208;41372303);湖南省自然科学基金(2015JJ3069)

摘　　要：针对深厚软黏土地基一维固结计算中,土体初始应力和附加应力分布形式对地基固结度存在较大影响的问题,假设土体初始应力沿深度变化、外荷载引起的附加应力随时间和深度变化、土体应力应变关系满足双曲线模型,推导了均布荷载下软土地基的一维非线性固结控制方程,并采用差分法求解,得到了地基固结度及沉降计算公式。算例分析表明,该方法计算所得地基固结度与传统解析解吻合良好,且在时间维度上分段计算可有效提高差分法计算效率;采用该方法计算地基沉降所得结果与实测数据吻合较好,且能大幅度简化固结计算过程,具有较好的工程应用价值。In the calculation of one-dimensional soft clay ground consolidation in deep soil, initial stress and additional effective stress distributions in soil greatly influence the degree of consolidation of ground. With regard to this problem, one-dimensional nonlinear consolidation governing equations of soft ground under uniform loads are derived and solved with the finite difference method, based on the assumptions that the initial stress in soil varies with the ground depth, and the additional effective stress caused by external loads changes with both ground depth and consolidation time, as well as the hyperbolic model of the soil stress-strain relationship. Formulas for the degree of consolidation and settlement of ground are presented. A case study shows that the degree of consolidation of ground calculated with the finite difference method agrees with the traditional analytical solution, and the computational efficiency of the finite difference method can be effectively improved when the segmental calculation method is used throughout the consolidation process. The results of another example show that the settlement of ground calculated with the finite difference method agrees with the in-situ data. The suggested method can greatly simplify the consolidation calculation and is of high applicative value in engineering.

关 键 词：软黏土 一维固结 非线性 有限差分法 均布荷载 双曲线模型 

分 类 号：TU447[建筑科学—岩土工程]