真空预压法加固软基的流固耦合数值分析

利用数值分析方法建立了软土地基模型，采用比奥固结理论，计算分析了真空预压下的软土地基流固耦合作用；并进一步分析了真空度损耗率、密封墙、塑料排水板打设深度等因素对软基加固效果的影响。分析结果表明:在抽真空早期，地表沉降增长很快，达到一定天数后，沉降值逐渐趋于稳定；真空负压沿深度、水平方向上损耗，在加固软土外围形成一个零孔隙水压力面；真空度损耗率、塑料排水板打设深度对真空预压加固软土的效果影响很大；侧向密封墙对加固区内土体影响不大，但其限制了真空负压的侧向传递，使影响区的地基沉降大幅减小。

Fluid-structure coupling numerical analysis of soft soil reinforced by vacuum preloading method

A numerical model of soft soil reinforced by vacuum preloading method was established, and the fluid-structure coupling interaction of the soft soil was calculated based on Biot consolidation theory. Then the influence of vacuum loss, sealing wall and the depth of prefabricated vertical drains (PVDs) on the subsoil surface settlement was analysed. The settlement of the subsoil increased rapidly at the early days of vacuum preloading and became stable after certain days. Vacuum negative pressure lost along the vertical and horizontal directions with a zero pore water pressure surface forming in the periphery of the reinforced soft soil. The vacuum loss and the depth of the PVDs had a great effect on the settlement of the soft soil, while the lateral sealing wall exerted little influences. The sealing wall blocked the lateral transfer of the vacuum negative pressure, and reduced the subsoil settlement of the influential area.