土压平衡盾构参数对隧道地表沉降影响研究

Study on influence of shield parameters ontunnel ground settlement in EPB shield construction

以哈尔滨市轨道交通3号线二期工程海河东路站-先锋路站区间为工程背景,研究了土压平衡盾构参数对隧道地表沉降的影响。首先基于现场监测数据,引入灰色关联模型分析盾构施工主要参数与隧道地表沉降值间的灰色关联度;而后参考关联度排序结果,选取土仓压力、注浆压力和掘进速度3个主要掘进参数设计正交模拟试验;最后根据数值模拟结果,应用方差分析和极差分析进一步确定盾构参数的主次关系和显著性,并与灰色关联分析结果相互验证。正交试验分析结果表明:该工程区间段盾构参数对变形稳定后地表沉降影响从大到小的顺序为:土仓压力、掘进速度、注浆压力,与灰色关联分析结果一致。基于正交试验得到优化的水平组合为:土仓压力180 kPa、掘进速度30 mm/min、注浆压力0.3 MPa。实地监测结果表明该水平组合在现场施工中具有很好的效果,可为类似工程盾构施工参数优化和沉降控制研究提供借鉴。

Based on the shield tunnel between Haihe East Road station to Xianfeng Road Station of Harbin Metro line 3 phase II project,this paper studied the influence of different shield parameters on the tunnel ground settlement in EPB shield construction.Firstly the grey relation model was introduced to analyze the grey correlation degree between the main shield parameters of shield construction and the ground settlement value of the tunnel by using the field monitoring data.Then referring to the ranking results of correlation degree,an orthogonal simulation experiment was designed by selecting three main tunneling parameters,such as soil chamber pressure,grouting pressure and tunneling speed.Finally,according to the results of numerical simulation,variance analysis and range analysis were used to further determine the primary and secondary relationship and significance of shield parameters,which were mutually verified with the results of grey correlation analysis.The experiment results showed that the order of the influence of shield parameters on the ground settlement after deformation stabilization was:soil chamber pressure>tunneling speed>grouting pressure,which was consistent with the results of grey correlation analysis.Based on the orthogonal experiment,the optimal level combination was as follows:180 kPa of soil chamber pressure,30 mm/min of tunneling speed,0.3 MPa of grouting pressure.The field monitoring results showed that this level combination had a good effect in the field construction,which can be used as reference in the study of shield construction parameter optimization and settlement control of similar projects.