高速铁路泡沫混凝土路基结构稳定性能试验研究  

Experimental Study on the Stability Performance of Foamed Concrete Subgrade Structure in High-Speed Railway

作　　者：姜贺 JIANG He(Lunan High-Speed Railway Co.,Ltd.,Jinan 250000,China)

机构地区：[1]鲁南高速铁路有限公司,山东济南250000

出　　处：《河南科技》2024年第22期72-77,共6页Henan Science and Technology

基　　金：山东铁路投资控股集团有限公司2023年度科技计划项目(TTKJ2023-14)。

摘　　要：[目的]通过进行室内模型试验,探究高速铁路工程中泡沫混凝土路基结构在工程应用中的可行性。[方法]将部分基床底层利用泡沫混凝土浇筑层进行替代浇筑大比例模型,通过施加静荷载及等频、等幅的动荷载测试泡沫混凝土路基结构的长期静、动力稳定性能。[结果](1)路基基床表层高度一致时,静载作用下随着测点与加载点水平、竖直距离的增大,测点处附加应力值不断减小,且在穿过泡沫混凝土层时应力降幅显著。(2)随着测点深度的不断增加,动应力衰减系数减小,动应力值不断降低。级配碎石层及泡沫混凝土层均存在显著的耗能作用,且级配碎石层对动应力的耗散程度高于泡沫混凝土A、B组填料层。(3)当级配碎石层厚度分别为0.5 m和0.7 m时,在循环动应力加卸载作用下泡沫混凝土层累积变形分别占整体累积沉降的3.18%和3.80%,泡沫混凝土作为整体浇筑填料不产生较大的塑性变形,变形主要由级配碎石层产生。[结论]荷载作用下泡沫混凝土路基结构具备良好的减力、耗能及抗变形性能。研究成果可为今后类似工程提供试验参数依据。[Purposes]In order to explore the feasibility of foamed concrete subgrade structure in high speed railway engineering,laboratory model test method was established to make the test.[Methods]The foam concrete layer is used to replace the large scale model for part of the foundation bed,and the long-term static and dynamic stability of the foamed concrete subgrade structure is tested by applying static load and constant frequency and amplitude dynamic load.[Findings]①When the surface height of the subgrade is the same,the additional stress at the measuring point decreases with the increase of horizon-tal and vertical distance between the measuring point and the loading point under static load,and the stress decreases significantly when passing through the foamed concrete layer.②The attenuation coeffi-cient of dynamic stress decreases and the value of dynamic stress decreases with the increasing depth of measuring point.Both graded gravel layer and foamed concrete layer have significant energy dissipation effect,and the degree of dissipation to dynamic stress of graded gravel layer is higher than that of foamed concrete layer than that of group A and B packing layer.③When the thickness of graded gravel layer is 0.5 m and 0.7 m,the cumulative deformation of foamed concrete layer under cyclic dynamic stress load-ing and unloading accounts for 3.18%and 3.80%of the total cumulative settlement,respectively.Foamed concrete as a whole packing does not produce large plastic deformation,the deformation is mainly caused by graded gravel layer.[Conclusions]The foamed concrete subgrade structure under load has good performance of reducing force,energy dissipation and deformation resistance.The research re-sults can be used as reference for similar engineering upgrading test parameters in the future.

关 键 词：高速铁路 泡沫混凝土 路基结构 附加应力 动应力 累积沉降量 

分 类 号：U213[交通运输工程—道路与铁道工程]