砂井地基堆载沉降的PFC2D模拟

砂井是利用土的排水固结原理来处理软弱地基的代表性施工技术。针对现有的软基沉降计算和预测方法存在的不足,利用离散单元法中二维颗粒元法PFC2D建立了砂井二维模型,对砂井地基堆载沉降过程进行二维离散元仿真模拟。采用由2～7个不同组合方式的簇单元来体现软基的孔隙率,改进了PFC2D中的水位降深模型,分析了软基沉降过程中水位的变化规律。模拟与现场实测结果的对比表明:模拟沉降值与实测值基本吻合。

PFC2D simulation of settlement on heaped load with sand-drained grounds

Sand drain is the representative construction technology for ground treatment by drainage consolidation to deal with the soft foundation. The usual settlement calculation for the soft foundation and the prediction method are defective. Using PFC2D, we set up a two-dimensional model and simulate the process of settlement on heaped load for sand-drained ground with two dimension discrete element. Using 2~7 cluster units of different combination modes, we embody the porosity of the soft foundation, improve the model and analyze the changing rule of water level in the settlement process. The computed results basically tally with the measured ones.