【摘要】 二次衬砌作为Ⅲ类以下围岩隧道的主要承载结构和最后一道防水防线,其结构安全对隧道工程质量起着至关重要的作用。首先根据公路隧道设计规范和普氏地压理论,对某高速公路隧道围岩压力进行计算,为现场二次衬砌压力实测值提供了可比较的参考标准。然后,根据二次衬砌压力实测值,应用同济曙光软件对最大实测压力断面二次衬砌结构内力进行数值计算,根据规范对二次衬砌轴力和剪力设计值进行计算,并基于数值计算结果对二次衬砌进行了结构强度校核。最后结合隧道设计、工程地质、施工及地质雷达探测情况,分析了该隧道加宽段及其附近二次衬砌压力明显偏大和产生细小裂缝的原因。更多还原

【Abstract】 Safety of secondary lining is of utmost importance to tunnel engineering quality as the main bearing structure and the last water-prevent line for rock types I,II,III. In this paper,firstly the rock stress on secondary lining of a freeway tunnel is obtained to provide a comparable criteria for its measured data,according to design specification of highway tunnel and P′ theory. Then the secondary lining strength in maximal measured-stress s face is checked on the basis of numerical results of internal stress obtained by using GeoFBA code of Tongji University and design specification of highway tunnel. Finally,the reasons of the induced microcracks are listed after consideration of design parameters,given engineering case,and construction speed.更多还原