蒙华铁路阳城隧道土石分界处地层大变形机理分析及整治措施

Mechanism Analysis and Treatment Measures of Large Deformation in Soil-Stone Demarcation Stratum of Yangcheng Tunnel in Mengxi-Huazhong Railway

蒙华铁路阳城隧道在穿越土石分界处时出现了软岩大变形,严重影响到施工安全和进度。采用室内试验和理论分析,从围岩物理力学性能、工程地质和水文地质条件、施工及人为因素等方面对土石分界处地层大变形机理进行了分析。结果表明,此次大变形是由不良地质和施工共同作用所致。针对大变形提出了反压回填、加密降水、注浆加固、换拱以及设置横撑的整治措施。

The large deformation of soft rock occurred in Yangcheng tunnel of the Mengxi-Huazhong Railway crossing the soil-stone demarcation stratum,which seriously affected the construction safety and progress.The mechanism of large deformation in soil-stone demarcation stratum was analyzed from aspects of physical and mechanical properties of surrounding rock,engineering geology and hydrogeological conditions,construction and human factors by using indoor test and theoretical analysis.The results show that the large deformation is caused by both bad geology and construction condition.The treatment measures such as reverse pressure backf illing,encrypted precipitation,grouting reinforcement,changing arch and setting transverse braces are put forward according to the large deformation.