摘要
双连拱公路隧道施工工序复杂,会导致隧道围岩遭受多次扰动,不良地质条件以及不合理的施工工序都会导致衬砌裂缝的出现,裂缝的出现对隧道结构的整体受力以及隧道防水等都十分不利。以云南元磨高速公路三公箐隧道为背景,结合隧道的裂缝监测工作,指出混凝土温度、不均匀沉降、偏压荷载、不合理的施工工序均是双连拱隧道裂缝的主要成因。对隧道结构影响较大的是不均匀沉降、偏压荷载和不合理施工工序诱发的裂缝。针对双连拱隧道施工中出现的裂缝,根据其不同成因,可分别采用严格混凝土配合比、加强振捣和养护、设置变形缝地基补强、加强中隔墙中导洞的侧壁支撑、加固变形边坡、消除偏压、洞内注浆加固以及地表注浆加固等方法进行处理。
The complex construction procedure of twin-arc highway tunnels often leads to repeated rock disturbances. Unfavorable geological conditions and improper working procedures may also cause cracking in tunnel linings, thus create difficulties for groundwater inflow prevention and stability. The Sangongqing tunnel on the Yuanjiang-Mohe highway in Yunnan province is taken as a typical example and analyzed for the main factors of cracking of tunnel lining based on the observed monitoring data. It is found that the concrete temperature, non-uniform settlement of the tunnel floor, uneven pressure, and improper construction sequence, are the main causes for the cracks of twin-arc tunnel. Among them, the non-uniform subsidence of the tunnel floor, the uneven pressure, and the improper construction sequence, are the main factors influencing the stability of the twin-arc tunnels. For treatment of cracks of the twin-arc tunnels, according to their different causes, different measures can be adopted: (1) more strict control on the mix proportion of concrete; (2) improved quivering and cure of concrete; (3) using artificially installed deformation joints in the linings; (4) reinforcing the tunnel floor; (5) improved support of connection passes in the separation pillar; (6) supporting the deforming slopes of tunnels to eliminate uneven pressures; (7) grouting (from ground surface or in tunnel) to reinforce the weak surrounding rock.
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2005年第2期195-202,共8页
Chinese Journal of Rock Mechanics and Engineering
基金
西部交通建设科技项目(2002–318–000–22 及 2003–318–490–18)
重庆大学西南资源开发及环境灾害控制教育部重点实验室资助项目
