偏压连拱隧道病害分析及治理措施

基于某高速公路偏压连拱隧道衬砌发生严重破坏和隧道上方发生较大规模的山体开裂等病害,采用地震CT手段对隧道周围的工程地质进行了探测;根据现场监测数据,分析了隧道支护结构的受力状态及其安全性;对复杂地质条件下两种典型的施工方案进行了动态施工的数值模拟,对比分析了不同施工方案对围岩稳定和衬砌受力的影响;探讨了衬砌发生严重破坏的原因,并提出了相应的治理措施。研究结果表明:连拱隧道内侧断裂带、上方松散层等不良地质条件和不合理的施工方案是导致隧道衬砌严重破坏和山体地表开裂的主要原因。研究结果为分析和治理偏压连拱隧道病害提供了依据。

Research on defects of arcade tunnel with partial pressure and its treating measurements

Based on severe cracks induced on linings and surface clefts on the mountain in some freeway arcade tunnel with partial pressure,firstly,seism CT method was adopted to detect the engineering geology around the tunnel; secondly,the tunnel lining's stress state and safety were analyzed according to the in situ monitoring data;thirdly,two typical staged construction projects under the complicated geology conditions obtained by seism CT were numerically simulated and their influences on the rock stability and lining's stress were compared;finally,main causes to induce these defects were further discussed,and some corresponding treating measurements were put forward.The research results indicate that the top inclined fault and the loose rock strata and the unreasonable construction project are the main causes to induce these defects.The results provide theory for treating these defects in the freeway arcade tunnel.