隧道围岩与支护结构变形协调控制机理及工程应用

为解决高应力下隧道岩爆以及软岩大变形控制难题,本文从隧道围岩荷载与支护平衡、变形协调控制及围岩能量守恒三方面进一步分析地下工程平衡稳定方法的特点;根据不同围岩级别总结地下工程平衡稳定方法中隧道支护结构抗力与围岩变形特征曲线,并提出隧道围岩支护的施工建议;通过分析围岩与支护结构有效荷载传递规律与功能转换特征,揭示围岩平衡与支护结构变形协调控制机理,并结合高应变吸能层材料设计一种表征为“吸能让压 支承抗压”的一体化新型隧道围岩支护工艺。通过工程应用表明,基于新型支护工艺在岩爆、软岩大变形隧道中围岩压力降低28.09%,保障了隧道安全高效施工。

Investigation on Control Mechanism of Balanced and Coordinated Deformation of Tunnel Surrounding Rock and Application in Engineering

The characteristics of underground engineering balance theory were further analyzed from the three aspects of the load-support balance of tunnel surrounding rock, coordinated control of surrounding rock support and deformation, and rock conservation of energy in order to solve the problem of tunnel rockburst and large deformation of soft rock under high stress. According to surrounding rock grades, the theoretical characteristic curves of tunnel support structure resistance and surrounding rock deformation based on the equilibrium and stability theory of underground engineering were described; and the corresponding construction suggestions were also proposed. The suggested coordinated control method for the surrounding rock balance and support structure deformation was developed by evaluating the variation law of effective load and energy conversion characteristics of the surrounding rock and support structure. A new tunnel surrounding rock support device characterized as "energy absorption and pressure release, support and resist compression" was designed by combining with the high strain energy absorbing material. Finally, the application in engineering showed that the application of the new technology used in rockburst and soft rock large deformation tunnels reduced the surrounding rock pressure by about 28.09% and ensured the safe and efficient construction of the tunnel.