基于位移反分析法的隧道围岩参数反演研究

Inverse Analysis of Tunnel Surrounding Rock Parameters Based on Displacement Back Analysis Method

结合某公路隧道实例,在既有监测数据的基础上,对拱顶沉降监测数据进行了处理。根据ABAQUS有限元软件建立三维动态施工模型,将模型分成四部分：原始围岩区、管棚等效加固区,初次衬砌区和二次衬砌区,选择原始围岩区本构模型为摩尔-库伦弹塑性模型,其他部分本构模型为弹性模型。根据实际情况和经验,对各部分参数进行了简化,选取围岩参数的弹性模量和泊松比进行了反演,并将反演结果与实测数据比较,相差不大,可为隧道的信息化施工提供参考。

This paper presents a case history of evaluation of the highway tunnel construction monitoring data at the crest of the tunnel.A three-dimensional tunnel excavation model was established by using commercial software ABAQUS.Four different regions are divided in the tunnel model：undisturbed virgin rock mass region,pilot perforated pile reinforcement region,initial lining support region and double lining support region.The Mohr-Coulomb elasto-plastic model was applied at the undisturbed virgin rock mass region and the elastic model was applied to other regions.The analytical parameters such as elastic modulus and Poisson＇s ratio were calibrated with the monitored data throughout the back analysis.The analytical results provided an effective way of predicting the performance of the tunnel excavation.