软岩大断面硐室动态施工与耦合支护技术研究

基于软岩大断面硐室的地质条件和破坏特征, 采用FLAC^3D软件分析了硐室围岩力学形态变化特征与破坏机理, 结合软岩大断面硐室稳定性控制理论, 提出了由初次高性能锚网喷支护、二次注浆及底板锚注支护形成的耦合支护方案, 并给出了详细的技术参数。通过耦合支护技术, 实现了硐室围岩的共同承载, 提高了支护结构的整体性和承载能力。工程试验结果表明: 该耦合支护技术有效地控制了硐室变形, 满足了软岩地层条件下大断面硐室的支护要求, 取得了较好的技术与经济效果。

Research on Dynamic Construction and Technology of Coupling Support for Underground Chamber of Soft Rock with Large Section

Based on geological conditions and failure characteristics of underground chamber of soft rock with large section, mechanical characteristics and failure mechanism for surrounding rock of chamber was analyzed with FLAC3D. In combination with control theory of stability for chamber of soft rock with large section, a coupling supporting program consisting of initial bolting and shotcreting, plus secondary grouting and floor bolting was proposed with detailed technical parameters. Load can be born cooperatively on the surrounding rock of chamber with this coupling support program, resulting in the integrity and bearing capacity of support structure enhanced. Engineering applications indicate that the chamber deformation can be effectively controlled with this coupling support technology, especially for the underground chamber of soft rock with large section, leading to good result in terms of technology and economy.