桩-锚支护在某临水泵站深基坑工程中的应用与分析

Application and Analysis on Pile-Anchor Bracing in Deep Foundation Pit Project of Pumping Station nearby Water

通过结合实际,介绍了桩-锚支护在临水深基坑工程中的设计应用。通过结合现场实测数据、三维有限元计算与现行规范中的m值法,分析了基坑开挖过程中锚索轴力、地表沉降与桩身位移的变化。结果表明,在本工程中,m值法无法真实反映锚索张拉导致拉锚系统内力重分布的过程。m值法计算得到的桩身最大位移值与实测数据较为接近,而有限元法计算得到的地表沉降发展规律和桩身变形曲线形状与实测数据较为吻合。因此,实际基坑工程设计中,在采用现行规范中m值法进行设计的同时,宜辅以有限元计算分析,以便对基坑围护变形有较为准确的判断。

Combined with the practices,the design and application of the pile-anchor bracing in a deep foundation pit project nearby water are introduced.Through the field measured data,three-dimensional finite element calculation and m-value method in the current specification,the variations of anchor cable axial force,ground surface settlement and pile body displacement are analyzed.The result shows that the m-value method is hard to really reflect the process of redistribution of internal force in the anchor system caused by anchor cable tension.The maximum displacement value of pile body calculated by m-value method is closer to the measured data,and the ground surface settlement development law and the pile body deformation curve shape calculated by the finite element method are more identical with the measured data.Therefore,in the actual design of foundation pit engineering,at the same time to use the m-value method in the current specification for design,it should be supplemented by the finite element calculation and analysis in order to judge the deformation of foundation pit bracing relatively accurately.