隔离桩对盾构侧穿建筑物时基础变形的影响分析

以济南地铁R1线地下段盾构近穿某建筑物为背景,采用数值分析的方法对隔离桩不同参数进行逐一模拟。研究了隔离桩不同桩长、桩洞距及桩间距对建筑物基础位移控制的影响。研究表明,桩长越长,隔离效果越好;在一定范围内,桩洞距越小隔离效果越好;由于桩间土拱效应,桩间距减小至一定程度后,隔离效果改善不明显。经优化选取桩长为30 m、桩洞距为2.0 m、桩间距为1.2 m的隔离桩。相比未打设隔离桩的情况,优化取值的隔离桩后,建筑物基础水平位移可减小36.6%,竖向位移可减小33.1%。

Impact Analysis of Isolation Piles on Foundation Deformation with Shield Construction Penetrating Buildings

According to the project on Jinan metro Line R1,the shield construction of which penetrates a business hotel,various parameters of isolation piles are studied by numerical simulation.Firstly,the influence of different pile lengths on foundation displacement control is studied by selecting the distance between the piles,pile spacings and the tunnels.The research indicates tha the longer the piles length,the better the effect of isolation;the smaller the distance between the piles and the tunnel,the better the isolation effect in a certain range.But the isolation effect of piles spacing will not be obvious due to the soil arch effect between the piles.Isolation pile is optimized to 30 m long,keeping 2.0 m distance between the piles and the tunnel with 1.2 m pile spacing.This method could decrease the horizontal displacement of building foundation by 36.6％ and vertical displacement by 33.1％.