隔离桩对浅埋暗挖隧道周边建筑物下沉的隔离效果研究

Study on the Isolation Effect of Isolated Piles on the Sinking of the Surrounding Buildings in the Shallow Tunnel

为了准确了解隔离桩结构体系在浅埋暗挖隧道施工过程中对周边建筑沉降的隔离效果,针对某地铁采用隔离桩保护隧道开挖区段周围建筑物工程,利用MIDAS-GTS软件进行了有限元优化分析研究。首先对比分析了有隔离桩和无隔离桩时隧道开挖对周边建筑物沉降的影响,然后分别研究了隔离桩桩长、桩径及桩间距等参数对建筑物沉降控制效率。由研究结果表明:隔离桩对建筑物沉降的控制效果随着桩长的增大逐渐变好,而桩径和桩间距的变化影响土体的微拱效应,会显著影响隔离桩对土体变形的隔离效果,同时也验证了本工程隔离桩所采用的设计参数组合是合理的。

In order to understand the isolation effect of the isolation pile structure system to the surrounding buildings in the construction of shallow buried tunnel,isolation piles are applied to protect surrounding buildings engineering at the subway tunnel excavation section,the finite element optimization analysis of the MIDAS-GTS software is carried out by using the finite element method. Firstly,the influence of tunnel excavation on the settlement of surrounding buildings is compared and analyzed when there are isolated piles and non-isolated piles. Respectively,the building settlement efficiency is researched based on the isolation pile length,pile diameter and pile spacing. The results of the study indicate that: The control effect of the isolation pile on the settlement of the building will gradually become better with the increase of the length of the pile,but the variation of pile diameter and pile spacing affects soil micro arch effect,which can significantly affect the isolation effect of the isolated pile to the soil deformation. At the same time,we also get the best design parameters of the isolated piles.