寒区格构梁与锚杆复合结构的冻胀效应计算方法  

A calculation method of frost heave effect of lattice beam and anchor composite structure in cold regions

作　　者：董建华[1,2] 柳珂[1,2] 董旭光 孙国栋[1,2] DONG Jianhua;LIU Ke;DONG Xuguang;SUN Guodong(Key Laboratory of Disaster Prevention and Mitigation in Civil Engineering of Gansu Province,Lanzhou University of Technology,Lanzhou,Gansu 730050,China;Western Engineering Research Center of Disaster Mitigation in Civil Engineering of Ministry of Education,Lanzhou University of Technology,Lanzhou,Gansu 730050,China)

机构地区：[1]兰州理工大学甘肃省土木工程防灾减灾重点实验室,甘肃兰州730050 [2]兰州理工大学西部土木工程防灾减灾教育部工程研究中心,甘肃兰州730050

出　　处：《岩石力学与工程学报》2020年第5期984-995,共12页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家自然科学基金资助项目(51778275,51268037);甘肃省高等学校科研成果转化项目(2018D-07)。

摘　　要：为了研究寒区格构梁与锚杆复合结构变形和内力在冻胀作用下的变化规律,基于Winkler弹性地基梁理论,建立考虑冻胀作用的复合结构计算模型。考虑到土体与支护结构协调变形的特点,将土体的冻胀位移视为自由冻胀和复合结构约束冻胀两部分的叠加,推导出冻胀力计算公式,并采用有限差分法推导冻胀作用下格构梁变形和内力的计算公式。通过算例分析得出,考虑冻胀作用后复合结构的变形和内力十分显著,在寒区边坡支护工程设计时,应当考虑冻胀力的作用并预留足够的安全度。模型试验结果显示,格构梁位移、内力以及锚杆拉力的计算值与试验值分布规律及变化趋势基本一致,说明给出的冻胀效应计算方法合理、可行,为寒区格构梁与锚杆复合结构的分析与设计提供了一种新的思路。In order to study the variations of the deformation and internal force under frost heave effect of lattice beam and anchor composite structure in cold regions,a calculation model of the composite structure considering frost heave is established basing on Winkler elastic foundation beam theory. Considering coordinated deformation of the soil and the support structure and regarding the frost heave displacement of soil as the superposition of free frost heave and constrained frost heave,a calculation expression of frost heave force is given,and calculation formulas of deformation and internal force of lattice beam under frost heave effect are derived by using the finite difference method. An example is illustrated,and it is shown that the displacement and internal force of the compound structure is very significant while considering frost heave effect,which indicates that the frost heaving force should be considered and enough safety margin should be set aside for the design of permafrost slope supporting projects. Comparisons between the model test results and the theoretical calculation show that the values of displacement and internal force of the lattice beam and the anchor tension are basically consistent as well as their variation trends,which indicates that the calculation method of frost heave effect is reasonable and feasible and provides a new idea for the analysis and design of the compound structure of lattice beam and anchor in frozen soil areas.

关 键 词：土力学 寒区边坡 格构梁与锚杆复合结构 冻胀作用 弹性地基梁 有限差分法 

分 类 号：TU43[建筑科学—岩土工程]