隧道衬砌强度沿厚度变化规律及模板台车设计理念探讨

Discuss on Change Rule of Tunnel Lining Strength along Thickness and Design Philosophy of Formworking Jumbo

隧道衬砌强度检测常采用回弹法和钻芯法,两种方法检测的对象分别是混凝土表面和结构内部,回弹法的检测强度普遍高于钻芯法,对此,为查明出现这种差异的原因,采用回弹法和钻芯法对新建隧道衬砌强度进行了一系列检测和试验,经回归处理并结合数值模拟分析,研究结果表明:衬砌强度沿深度方向呈先缓慢降低而后加速下降再趋于平稳的变化趋势;衬砌表面回弹法检测强度R1、钻芯强度R2与钻芯拟合强度R3之间满足R1=β1R2和R3=β2R2,并提出了检测工程中β1,β2的建议值;根据模拟结果,探讨了整体式衬砌模板台车的设计理念。

Rebound method and core drilling method are often used to check the strength of tunnel lining.Their testing objects are concrete surface and structure interior,respectively.The strength value obtained from rebound method is generally higher than that from core drilling method.In order to find the cause of the difference,the both methods were hereto used to conduct a series of strength detection and tests on the newly built tunnel lining.After regression processing and numerical simulation analysis,the research results show that,the strength of tunnel lining presents a change trend along the depth direction,i.e.at first decreasing slowly,then dropping off sharply,and leveling off at last;among the strength R 1 from rebound method,the strength R 2 from core drilling method,and the fitting strength R 3 from core drilling,they relate proportionally to meet R 1=β1 R 2 and R 3=β2 R 2,with the proposed value ofβ1 andβ2 put forward in the testing works.Finally,according to the result of simulation,the design philosophy of integrated lining form jumbo was discussed.