高速铁路隧道进口段地质灾害协同处治技术

Collaborative Treatment Technology for Landslide and Tunnel Diseases at the Entrance Section of the TaShao Village Tunnel in Baoji-Lanzhou High-speed Railway

为解决宝兰高速铁路塔稍村隧道穿越古滑坡体施工过程中进口仰坡变形、滑坡,洞内衬砌开裂、错台等问题,通过现场调查和监测,分析隧道洞口地表及结构开裂破坏特征及成因,提出进口段滑坡体-隧道灾害协同处治技术,并对实施效果进行现场测试。研究表明:古滑坡体水文地质条件较差、大断面隧道施工扰动、隧道支护结构承载力不足是导致隧道洞口变形破坏的主要原因,通过在洞外施作预应力锚索格梁和预加固桩,洞内径向注浆加固、拆换初支及二衬,支护加强及参数动态调整等协同处治技术,增加了隧道进口段古滑坡体的稳定性,有效控制了洞口边仰坡变形的发展,提高了隧道结构安全性。

In order to solve problems including slope deformation,landslide,lining cracking,wrong platform at the entrance of the TaShao village tunnel in Baoji-Lanzhou High-speed Railway during the construction through the ancient landslide,based the field investigation,monitoring and analysis methods,the characteristics and causes of crack disasters of surface-structure in tunnel portal were studied.The collaborative treatment technology for landslide and tunnel diseases was discussed and field tests on the implementation effect were carried out.The results show that,the main causes of the deformation and cracking of the inverted slope at the entrance of the TaShao village tunnel include:the geological and hydrological conditions of the ancient landslide,the construction disturbance of the large section tunnel,the thrust and confining pressure generated by the landslide and the insufficient bearing capacity of the tunnel support structure.The safety of the ancient landslide in the entrance of the tunnel is maintained and the development of the slope deformation at the entrance side of the tunnel is effectively controlled by applying measures such as driving pre-reinforced piles and prestressed anchor girders outside the tunnel,applying the radial grouting reinforcement inside the tunnel,removing and replacing the primary support and secondary lining,strengthening the support and adjusting dynamic parameters.