公路隧道衬砌背后缺陷风险评估研究

Risk Assessment on the Defects behind Lining of Road Tunnels

衬砌背后缺陷是隧道工程的常见病害之一,具有隐蔽性、复杂性和不确定性等特点,因此就衬砌背后缺陷存在时的隧道结构风险评估进行了研究。对衬砌背后缺陷进行辨识和分析,确定缺陷发生的概率,同时对一个二维圆形公路隧道模型设置不同位置且大小不同的各种背后缺陷,数值模拟得出这些缺陷对衬砌结构内力的影响,从而建立其后果的严重程度,再采用风险矩阵得出风险等级。在此基础上以某公路隧道为例,就存在的衬砌缺陷对该隧道结构进行具体的风险评估。衬砌背后存在缺陷时,衬砌的内力会大幅增长,使得结构面临很大的破坏风险,采用风险评估的方法得出具体的风险等级,从而正确定位缺陷,可以更加直观地看出衬砌背后缺陷对隧道结构的危害。

The rear defects are one of the common diseases of tunnel engineering with the characteristics of being latent,complexity,uncertainty and so on.So risk assessment on tunnel engineering with rear defects in the lining is significant.The rear defects were identified and analyzed,and their occurring probabilities were ascertained.Then,numerical simulations were conducted on a two-dimensional,circular tunnel model with a series of different defects placed in different location of the lining,the influence of the defects on the internal forces of the lining was gained,by which consequence severity was obtained and their risk ranks were achieved with risk matrix.Finally,taking a certain road tunnel as an example,the tunnel engineering with defects was assessed by risk assessment theory.It is concluded that the lining＇s internal forces will increase substantially when there exist defects behind the lining of the road tunnel,which causes the lining to face great breaking risk.The hazards of the rear defects to tunnel engineering can be easily found out by the risk ranks.