盾构隧道近距离通过高层建筑物时隔离桩参数优化设计

Optimization Design of Isolation Pile Parameters in Shield Tunneling for the Control of Deformation of High-Rise Buildings

运用FLAC3D数值模拟方法,研究了太原地铁2号线双塔西街—大南门区间隧道盾构施工扰动效应;以桩长、桩径、桩间距为因素,以建筑物沉降和倾斜程度为指标,采用正交试验方法对隧道近距离通过某高层建筑时隔离桩的作用规律进行了研究,并对隔离桩参数进行了优化分析。结果表明,合理选取参数有利于控制建筑物的变形,隔离桩参数对建筑物变形影响显著程度由高到低依次为桩间距、桩长、桩径;兼顾建筑物变形控制和施工成本控制的综合效果,根据九次正交试验的结果,本隔离桩工程的最优参数为:桩间距1.2m,桩长30m,桩径800mm。

The shield tunnel construction disturbance effects of Taiyuan Metro Line 2 Shuangtaxi Street-Dananmen interval were studied by FLAC3D numerical simulation method. With pile length, pile diameter and pile spacing as factors, subsidence and tilt rate as indexes, orthogonal test method was used to study the effect of isolation pile on tunnel which closely passes high-rise building, and the parameters of the isolation pile were optimized. The results show that the reasonable selection of parameters is beneficial to controlling the deformation of buildings. For the building deformation, pile spacing is the first influence factor; the second one is the pile length and the third one is the pile diameter. From the comprehensive effects of deformation control and construction cost control, the obtained pile spacing is 1.2 m,pile length is 30 m,pile diameter is 800 mm.