摘要
依托港珠澳大桥珠海连接线拱北隧道的深基坑工程,针对海域环境中基坑工程的渗流破坏问题,展开渗流特性研究。基于流固计算理论,利用PLAXIS计算程序,采用了摩尔库伦与PLAXIS自带的硬化(HS)模型对常水头、海流与潮汐作用下基坑周围渗流特性进行了系统深入的研究。结果表明,相对高频的波浪作用对临海基坑周围的渗流性状、基坑稳定影响较小,潮汐作用对支护墙侧的孔压波动有一定影响,对支护墙上的水土压力、墙身内力和变形、基坑的稳定性影响均较小。当考虑承压水层的水位与海水相通的时候,开挖过程中部分支护剖面的施工工况有发生承压水突涌破坏的危险,工程设计中可以采用简化解析解计算公式分析基坑开挖全过程支护结构两侧的稳态渗流问题。研究结果可为海域环境基坑稳定性控制技术提供理论依据。
Relying on the deep foundation pit project of Gongbei Tunnel of Zhuhai Link line for Hongkong-Zhuhai-Macao Bridge,a study on seepage characteristics is carried out for the problem of seepage damage from the project of the foundation pit in seaward environment.Based on the theory of fluid-solid calculation,the characteristics of the seepage around foundation pit under the effects of constant head,ocean current and tide are systematically and deeply studied herein through the built-in hardening soil(HS)model of Mohr Coulomb and PLAXIS with the calculation program of PLAXIS.The study result shows that the impact from the relatively high frequency wave effect on the seepage behavior and foundation pit stability around the seaward foundation pit is less,while the tidal effect has a certain impact on the fluctuation of the side pore pressure of the supporting wall,but has less impact on the water-earth pressure on the supporting wall,the internal force and deformation of the wall body and the stability of the foundation pit.When the connection of the artesian aquifer water level with sea water is considered,the damage from the confined water sudden surge is to occur under the construction condition of a part of the supporting-sections during the excavation;for which the problem of the steady seepages from both the sides of the supporting structure during the whole excavation process of the foundation pit can be analyzed with the simplified analytical solution formula in the engineering design.The study result can provide the theoretical basis for the technology of controlling the stability of the foundation pit in marine environment.
作者
李健
范方方
LI Jian;FAN Fangfang(CCCC Second Highway Consultants Co..Ltd.,Wuhan 430056,Hubei,China)
出处
《水利水电技术》
北大核心
2019年第7期202-208,共7页
Water Resources and Hydropower Engineering
基金
中交股份科技项目(KJFZ-2011-002)
关键词
临海环境
渗流特性
本构模型
海浪作用
潮汐作用
seaward environment
seepage characteristics
constitutive model
wave effect
tidal effect
