多年冻土区框架热锚管边坡支护结构的提出及简化设计方法初探

摘要

为解决多年冻土区冻融循环及全球气温升高引起的边坡失稳问题,基于"主动冷却"保护冻土的理念,结合框架锚杆和热棒制冷技术,提出一种既可主动降温、又能锚固支挡、还能减轻冻胀破坏,且适用于多年冻土边坡的新型支护结构,并阐述其技术原理;提出极限承载力和热量平衡两个设计控制指标,给出热-力共同控制的设计计算方法.将该结构和相应的计算方法应用于工程实例,计算结果表明:所提出结构不仅能防止多年冻土边坡上限退化,甚至能抬升上限,进而提高冻土边坡的稳定性;给出的计算方法能够较为准确描述结构的工作机理,为该结构的设计提供理论依据和参考.%In order to solve the slope failure caused by the freeze-thaw cycles and global temperature rising in permafrost regions,based on the idea of active cooling for permafrost protection,combined with the frame-anchor and heat pipe cooling technology,a new supporting structure applicable to permafrost slope was proposed,which can provide active cooling and anchor retaining functions,and can reduce the frost heaving damage.The technical principle of the new structure was described.The design control indexes of ultimate bearing capacity and heat balance,and the calculation method of thermo-force combined control for the structure were put forward.The structure and the corresponding calculation method were applied to a construction project.The results show that the proposed structure can prevent the degradation of the upper limit of permafrost slope,uplift the limit and improve the stability of permafrost slope.The method can describe accurately the working mechanism of the structure,which provides a theoretical basis for the design of the structure.