破碎岩层浅埋偏压双线隧道最优净距研究

Study on Construction Stability of Double-track Tunnel with Small Clear Distance under Complex Bias

基于峨汉高速林家埂隧道洞口端沟谷复杂偏压段和临近成昆线隧道段为工程背景,通过建立V级围岩条件下复杂偏压小净距隧道数值计算模型,对比分析不同净距条件下双线隧道施工过程中的围岩应力的演变规律及相互之间的力学影响,综合对比不同净距条件下围岩变形特点和塑性应变大小,得到艰险山区复杂偏压双线隧道合理净距,以期为类似条件下的山区大断面浅埋偏压双线隧道工程设计和施工提供有益借鉴和参考。

Based on the complex unsymmetrical pressure section at the entrance end of Linjiageng Tunnel of E-Han Expressway and the tunnel section adjacent to Chengdu-Kunming Line,through establishing the numerical calculation model of the complex unsymmetrical pressure small clear distance tunnel under the condition of V-class surrounding rock,the evolution law of surrounding rock stress in the construction process of double-line tunnel under different clear distance conditions and the mechanical influence between them are compared,and the deformation characteristics of surrounding rock under various working conditions are comprehensively compared.After optimization,the reasonable clear distance of complex unsymmetrical pressure double-line tunnel in difficult and dangerous mountainous areas is obtained,with a view to providing shallow buried double-line with unsymmetrical pressure for large sections in mountainous areas under similar.