CA砂浆层破坏对无砟轨道结构受力特性影响  

Influence of CA Mortar Layer Damage on Mechanical Characteristics of Ballastless Track Structure

作　　者：赵丽华 胡安泽 孟庆武 张吉松 ZHAO Lihua;HU Anze;MENG Qingwu;ZHANG Jisong(School of Civil Engineering,Dalian Jiaotong University,Dalian 116028,China;Liaoning Jianzhu Vocational College,Liaoyang 111000,China)

机构地区：[1]大连交通大学土木工程学院,大连116028 [2]辽宁建筑职业学院,辽宁辽阳111000

出　　处：《铁道标准设计》2024年第1期44-50,共7页Railway Standard Design

基　　金：国家自然科学基金项目(52108402);辽宁省教育厅科学研究支持项目(JDL2019018)。

摘　　要：CA砂浆层掉块破坏是无砟轨道结构运营过程中最突出的病害之一,其破坏程度对无砟轨道结构运营的安全性与适用性具有重要影响。通过采用修正Burgers模型转换Prony级数表征CA砂浆的黏弹性,建立CRTSⅠ型板式无砟轨道结构三维有限元模型,通过模拟CA砂浆层在板端和板中不同区域薄层掉块,研究车轮荷载作用下不同掉块位置、不同掉块大小对无砟轨道结构动力特性和结构位移的影响,分析掉块处轨道结构损伤演变规律和趋势,给出破坏界限建议值,为无砟轨道结构的养护维修提供理论依据和指导。研究结果表明:无论板端还是板中掉块,CA砂浆层破坏造成轨道板垂向加速度、垂向位移和纵向拉应力增幅明显,CA砂浆层掉块边缘位置的压应力急剧增大,而底座板垂向位移及受力逐渐减小;车轮荷载作用下,CA砂浆层板端薄层掉块达到0.9125m,板中掉块达到1.25 m时,轨道板的垂向振动和CA砂浆的压应力将会显著增大,应及时对轨道结构进行检修,避免轨道结构破坏快速扩展。CA mortar layer falling is one of the most prominent diseases in the operation of ballastless track structure,and its damage degree has an important impact on the safety and applicability of ballastless track structure operation.The modified Burgers model is used to convert Prony series to characterize the viscoelasticity of CA mortar,and a three-dimensional finite element model of CRTS I-type slab ballastless track structure is established.By simulating the thin layer falling off of CA mortar layer at the end of the slab and in different areas of the slab,the effects of different falling off positions and sizes on the dynamic characteristics and structural displacement of ballastless track structure under wheel load are studied,and the evolution law and trend of track structure damage at the falling off point are analyzed,The recommended value of damage limit is given,which provides theoretical basis and guidance for the maintenance of ballastless track structure.The research results show that no matter the slab ends or the slab is broken,the CA mortar layer damage causes significant increases in the vertical acceleration,vertical displacement and longitudinal tensile stress of the track slab.The compressive stress at the edge of the CA mortar layer is sharply increased,while the vertical displacement and stress of the base plate are gradually reduced.Under the action of wheel load,when the thin layer of CA mortar plate ends drops to 0.9125 m,and when the drop in the plate reaches 1.25 m,the vertical vibration of the track plate and the compressive stress of CA mortar will increase significantly.The track structure should be repaired in time to avoid rapid expansion of the track structure damage.

关 键 词：无砟轨道 CA砂浆层 黏弹性 掉块破坏 动力特性 

分 类 号：U213.2[交通运输工程—道路与铁道工程]