中文摘要：

沿海地区深基坑设计施工都十分重视其抗浮问题,在深基坑开挖前掌握抗拔桩对于基坑隆起和围护结构变形及受力规律十分重要,其研究成果对于节约工程成本和保证基坑施工安全具有重要的指导意义。以港珠澳大桥侧接线拱北海关隧道明挖段为依托,首先建立抗拔桩与土体的硬接触模型,并验证该模型对于抗拔桩模拟的合理性,采用极差分析法研究底板不同桩长和桩径加固对基坑围护结构稳定性的影响规律。分析结果表明,增大桩长可更有效地减小地表沉降,增大桩径可更好地控制连续墙的变形,增大桩长和桩径都可以很好地控制坑底隆起。

英文摘要：

Geotechnical engineers attach great importance to the uplift problem in design and construction of the deep foundation on the seaside. It is very important to know upheaval of foundation and deformation of support structure due to uplift pile before deep excavation, which can save the project cost and ensure the safety of construction. This case study how to deal with the excavation of open-cut section of Gongbei tunnel. The hard contact model of uplift pile and soil is established. And the simulated results are in good accordance with simulation of the uplift pile. Use the range analysis method to study the effect rule of deformation and stress of the whole support structure caused by the change of the length and diameter of pile. The results are obtained as follows: By increasing the pile length can be more effective to reduce the surface settlement; the larger the pile diameter is, the smaller the deformation of retaining wall is;Increasing the length and diameter of pile can control the upheaval of foundation effectively.