深埋非对称小间距隧道围岩压力计算方法

Calculation Method of Loosening Pressure for Deep-buried and Non-symmetry Closely-spaced Tunnels

基于深埋单洞隧道的普氏平衡拱理论,综合考虑左、右洞结构不对称和不同时施工的条件,提出了深埋非对称小间距隧道围岩压力分析模型,并推导了计算公式;运用推导的公式讨论了中夹岩柱厚度、隧道开挖跨度与高度、中夹岩柱抗压强度及加固系数对隧道围岩压力的影响规律;最后,结合工程实例将现场监测结果与计算结果进行对比分析,验证了分析模型和推导公式的合理性.

Based on the Pu,s sliding failure model of rock mass around a deep single tunnel,an analytical model of rock pressure for deep-buried and non-symmetry closely-spaced tunnels was proposed by considering asymmetrical structure and the construction processes. Meanwhile, based on the deduced formula,the causes that affect the rock pressure such as buried depth,rock pillars thickness,excavation span and excavation height were discussed. Finally, the comparison analysis was m a d e between monitoring data from practical tunnel engineering and theoretical values from the model. T he results show that the calculated model and the theoretical method proposed are rational and practicable. The experience and conclusions can be referred to the analysis of the design of supporting structure and reasonable construction scheme of deep-buried and non-symmetry closely-spaced tunnel.