复杂偏压小净距隧道围岩压力计算及参数影响性研究

为研究不同隧道净距及地表坡度对复杂偏压浅埋小净距隧道围岩压力的影响规律,引用公路隧道设计规范,建立围岩压力计算模型,推导出隧道围岩压力的理论计算公式;结合数值模拟验证了理论计算公式的合理性,讨论了不同隧道净距和不同地表坡度的参数值变化对先行洞和后行洞的拱顶、拱腰及拱脚围岩压力的影响规律。结果表明:在两洞先后开挖情况下,隧道净距及地表坡度的变化对隧道内侧围岩压力影响较大,并且先行洞内侧围岩压力同净距及坡度大小正相关,后行洞内侧围岩压力同净距及坡度大小负相关。研究结果可为类似隧道工程的设计和施工提供参考。

Surrounding Rock Pressure of Tunnel with Small Clear Distance under Complex Unsymmetrical Loading: Calculation and Parameter Impacts

A model for calculating surrounding rock pressure of tunnel with small clear distance under complex unsymmetrical loading is established. The theoretical formulas of surrounding rock pressure are deduced based on roadway tunnel design specifications to investigate the influence of clear distance and ground sloping on surrounding rock pressure of tunnel. The rationality of the theoretical calculation formulas are verified by numerical simulation. The influences of varying clear distance and ground sloping on the surrounding rock pressure of vault, arch waist and arch foot of the first tunnel and the subsequently excavated tunnel are analyzed. Results reveal that when two tunnels are excavated successively, the change of clear distance and ground surface sloping has great influence on the surrounding rock pressure inside the tunnel. The pressure of surrounding rock inside the first-excavated tunnel is positively correlated with clear distance and sloping, while the inner surrounding rock pressure of the subsequently excavated tunnel is negatively correlated with clear distance and sloping.