西安地铁施工诱发地表沉降及对城墙的影响

以西安地铁2号线为背景，利用3种预测公式对实测地表沉降值进行拟合，得到了沉降槽形态参数。利用拟合参数，借鉴“刚度修正法”原理对地铁下穿城墙施工诱发其基础的沉降进行预测，并建立城墙的三维有限元模型，对城墙所能承受的极限变形能力和承载力进行量化分析，分析结果表明：Peck公式能较好地描述地表沉降特征；考虑后期蠕变和固结作用，盾构施工所诱发的城墙基础最大沉降量不得超过20 mm，期望对后期地铁施工引起地表沉降及其对建筑物的响应提供科学参考。

Ground settlement caused by subway construction in Xi’an and its influence on the city wall

Based on Xi'an Subway Line 2, the settlement trough shape parameters are obtained by using three prediction formula to fit the measured surface settlement values. The fitting parameters and the " stiffness modification method " principle were carried out to forecast on the city wall foundation settlement induced by building subway under the city wall, meanwhile the three-dimensional finite element model of the city wall was established to do quantitative analysis of the ultimate deformation and bearing capacity. The results show that the Peck expressions can describe the character of the ground settlement well .And the ultimate settlement capacity induced of the city wall foundation shall not exceed 20 mm when considering creep and consolidation effect of the loess .This study is expected to provide a scientific reference to the ground settlement caused by underground construction and the response of buildings.