高速公路隧道衬砌纵向裂缝成因分析

Analysis of formation cause of longitudinal cracks in highway tunnel lining

针对某高速公路隧道运营后出现的纵向裂缝,通过裂缝调查,结合地质报告,运用有限元数值模拟的方法,建立在松散围岩荷载、水压力、形变压力作用下病害结构的计算模型,总结隧道衬砌裂缝产生的原因.研究结果表明:松散围岩荷载作为集中荷载,往往会导致作用部位的应力集中,衬砌内侧会出现较大拉应力而产生裂缝;水压力作用下衬砌结构承受较为均匀的压应力,往往在结构薄弱部位最先出现裂缝;形变压力作用下结构易产生纵向结构性受力裂缝.

Aimed at the longitudinal cracks appearing in a highway tunnel after running,based on the examination of the cracks,and according to the geological report,a computation model was established for the affected structure under loose rock load,hydraulic pressure,and deformation pressure by using finite element numerical simulation method.The formation cause of the tunnel lining cracks was summarized.The investigation result shows that the loose rock load as concentrated one will often lead to local stress concentration at the load application place,agreater tensile stress will appear at the inner side of the lining,producing lining cracks.Hydraulic pressure will cause more uniform compressive stress in the lining structure,so that the cracks will appear first at the weak place of the structure.Longitudinal structural stress cracks of structure will be easy to be caused by deformation pressure.