文章以长沙市湘江大道浏阳河水下隧道工程为依托,改进了以往数值方法在反映隧道流固耦合效应方面的不足,建立了同时反映岩土体力学特性和水体流动规律的流固耦合模型,基于弹塑性流固耦合效应,对明挖段基坑开挖进行了三维数值模拟。从而揭示出:基坑开挖至预定深度后,由于岩土体内渗流尚未达到稳定状态仍会继续发展,基坑变形及支护结构受力还会继续增长。这一研究结果为基坑支护及安全施工提供了技术支持。
With Liuyanghe tunnel in Changsha city as the back ground,authors ammended the shortcomings of current numerical methods considering fluid-solid coupling effect,put forward a new fluid-solid coupling model,taking account of both soil-rock mechanical characteristics and water flow and considering elasto-plastic fluidsolid coupling effect,carried out three dimensional simulation for the open pit excavation,analyzed the performance of the subaqueous tunnel during each construction stage.Owing to fluid-solid coupling effect,the displacements of the pit and internal forces in the supports will keep increasing during pit excavation.This provides technical support for the safety construction and supports for open pit excavation.