新建公路对既有隧洞的影响及粘钢加固效用分析

On the Influence of Newly-built Highway on Existing Tunnel and the Effect of Steel Bonded Reinforcement

以碧沙北路道路工程跨碧岭隧洞为例,研究了在既有隧洞上方修建公路时,车道荷载对隧洞衬砌结构的影响及粘钢加固方案的加固效果。采用非线性有限元的方法进行的数值模拟分析表明:新建公路会造成隧洞衬砌边墙凹陷、底板隆起、开裂增多等不利影响。粘钢加固后,钢板与衬砌共同受力,能有效减小衬砌变形,缓解衬砌应力集中,防止衬砌裂缝扩展,使得新增开裂占比从46.28%降至18.89%。

Taking the Bishabei Road project over the Biling Tunnel as an example,the influence of the traffic load of newly-built highway on the lining structure of existing underground tunnel and the effect of steel bonded tunnel reinforcement are analyzed.The results of nonlinear finite element analysis show that the newly-built highway will cause certain adverse effects on the tunnel such as sidewall depression,floor heave and increased cracking.While the steel plates and the lining will bear the load together with the steel bonded reinforcement,which can effectively reduce the lining deformation,relieve the lining stress concentration,prevent lining cracks from expanding and decrease the proportion of new cracks from 46.28%to 18.89%.