重载铁路基床污染级配碎石临界动应力及动强度特性研究  

Study on Critical Dynamic Stress and Dynamic Strength Properties of Fouled Graded Macadam in Heavy Haul Railway Subgrade Bed

作　　者：杨志浩[1,2,3] 岳祖润 叶朝良[1] 胡田飞[1,2] 介少龙 YANG Zhihao;YUE Zurun;YE Chaoliang;HU Tianfei;JIE Shaolong(State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures,Shijiazhuang Tiedao University,Shijiazhuang 050043,China;Key Laboratory of Mechanical Behavior Evolution and Control of Traffic Engineering Structures in Hebei,Shijiazhuang Tiedao University,Shijiazhuang 050043,China;School of Traffic and Transportation,Shijiazhuang Tiedao University,Shijiazhuang 050043,China)

机构地区：[1]石家庄铁道大学省部共建交通工程结构力学行为与系统安全国家重点实验室,河北石家庄050043 [2]石家庄铁道大学河北省交通工程结构力学行为演变与控制重点实验室,河北石家庄050043 [3]石家庄铁道大学交通运输学院,河北石家庄050043

出　　处：《铁道学报》2022年第7期145-153,共9页Journal of the China Railway Society

基　　金：河北省自然科学基金(E2020210044,E2020210006);省部共建交通工程结构力学行为与系统安全国家重点实验室课题(SKLQN2022-3,SKLYD2022-03)。

摘　　要：重载铁路基床表层级配碎石受细粒土侵入污染后服役性将大幅劣化,掌握循环荷载下污染级配碎石临界动应力及动强度的演变特征,对揭示路基病害的产生机理至关重要。首先,以不同细粒含量的级配碎石为研究对象,开展一系列不同应力水平条件下的大型动三轴试验,探究细粒含量、围压及动应力幅值对试样累积塑性应变及临界动应力的耦合影响机制。然后,基于塑性安定理论,对试样在不同条件下的变形行为进行划分,并进一步建立考虑围压及细粒含量参数的塑性蠕变状态临界动应力计算模型。最后,分析细粒含量及围压对动强度的影响规律,并通过归一化方法建立了静、动强度间的计算模型。研究成果可为基于强度控制原则的重载铁路新型路基结构设计提供参考。The serviceability of the graded macadam in heavy-haul railway subgrade bed will be greatly deteriorated after being invaded and polluted by fine-grained soil.Therefore,it is particularly important to understand the critical dynamic stress and dynamic strength evolution characteristics of fouled graded macadam under cyclic loadings.Firstly,taking graded macadam with different fine particle contents as the research object,a series of large-scale cyclic triaxial tests under different stress levels were carried out to investigate the coupling influence mechanism of fine particle content,confining pressure and dynamic stress amplitude on accumulative plastic strain and critical dynamic stress.Additionally,based on the plastic stability theory,the deformation behavior of specimens under different conditions was divided.Moreover,the calculation model for critical dynamic stress in plastic creep state considering the confining pressure and fine particle content parameters was further obtained.Finally,the influence properties of fine particle content and confining pressure on the dynamic strength were analyzed,and the calculation model between static and dynamic strength was established by normalization method.The research results can provide a reference for the newly heavy-haul railway subgrade structure design based on strength control principle.

关 键 词：重载铁路 污染级配碎石 细粒含量 临界动应力 动强度 

分 类 号：TU411.8[建筑科学—岩土工程]