泡沫混凝土换填处理低填道路下伏深厚软基的数值分析研究

Numerical Research on the Replacing Soft Soil by Foam Concrete to Treat Soft Foundation in Roadway

基于泡沫混凝土轻质高强的特点,提出泡沫混凝土超宽换填处理道路软基的方法。在弹性地基梁理论的基础上引入Boussinesq位移解,建立了一种求解置换层基底反力的理论计算方法。在Biot有效应力理论的基础上,通过Newton-Raphson方法计算位移和孔隙水压力迭代增量,同时以单元力和流量平衡建立控制方程,构建了地基固结沉降的数值计算方法。最后对比了置换层基底反力理论解与数值解,并分析了沉降的数值解,结果表明:(1)置换层基底反力的理论与数值计算结果基本吻合,证明该理论方法有效可行。(2)泡沫混凝土置换宽度存在最优值。

The disposal method of replacing soft soil with foam concrete by ultra-wide size to treat soft foundation in roadway was proposed based on the characteristics of foamed concrete about low density and high strength.The Boussinesq’s displacement solution was introduced on the basis of the elastic foundation beam theory to establish a theoretical calculation method for solving the foundation reaction force of replacement;The iterative increment of displacement and pore water pressure which was calculated by the Newton-Raphson method and the control equation which was established based on the force and flow balance of elements were used to construct the simulation method of consolidation settlement on the basis of the Biot’s effective stress theory.Finally,the theoretical and simulation results of the foundation reaction force are compared,and the settlement of foundation is analyzed,respectively.The results show that:(1)The theoretical results of foundation reaction force of replacement were basically consistent with the simulation results,which proves the effectiveness of the theoretical method.(2)There is an optimal value for the width of replacement.