超深圆形基坑施工过程的力学特性研究  

Study on Mechanical Property in Construction Process of Ultra-deep Circular Foundation Pit

作　　者：刘智勇[1] 许敬 张家国 任鹏[4] 

机构地区：[1]中国电建集团成都勘测设计研究院有限公司,成都610072 [2]成都市建筑设计研究院,成都610051 [3]成都市建工科学研究设计院,成都610051 [4]四川省建筑科学研究院,成都610081

出　　处：《路基工程》2016年第6期152-155,共4页Subgrade Engineering

摘　　要：依托德阳某超深圆形基坑项目,结合流固耦合理论,采用三维有限差分法对超深圆形基坑的施工过程进行动态数值模拟,对设计与施工方案进行了评估和优化。结果表明:由于支护桩间的高压旋喷桩的作用,圆形基坑开挖引起的排桩水平位移明显减小,而桩周的土层强度显著增大;降低圆形基坑周边土层中的地下水位,不仅可避免在施工过程中发生流土和管涌事故,还可在一定程度上降低工程开挖对土体的扰动。排桩的中下部弯矩比其他区域更大,因此,土体开挖至基坑的中下部位置时应特别注意。In relation to the ultra-deep circular foundation pit project in Deyang, the paper combined the fluid-structure interaction theory, and made the numerical simulation on the construction process thereof by 3D finite difference method, then assessment and optimization on the design and the construction scheme. The result shows that, due to the action of high-pressure jet grouting pile between the supporting piles, the horizontal displacement of piles in row caused by the excavation decreases greatly, and the strength of soil around the piles increases greatly; the drop of underground water level in the soil surrounding the circular foundation pit may not only avoid soil flow and piping accident in the construction process, but also reduce the disturbance to the soil mass by the excavation to certain extent. The bending moment in the middle and at the lower part of the piles is larger than that at other parts, hence, special attention should be paid when the excavation goes to the middle and lower part of the foundation pit.

关 键 词：超深圆形基坑 数值模拟 流固耦合 排桩 施工过程 

分 类 号：TU463[建筑科学—结构工程]