摘要
研究目的:CRTSⅡ型板式无砟轨道施工过程中,轨道板窄缝浇筑后纵连前,轨道板处于一种偏心受压状态,在温度荷载作用下轨道板容易产生上拱变形现象。本文利用ANSYS软件,建立温度荷载作用下CRTSⅡ型轨道板上拱变形有限元力学分析模型。通过对轨道板上拱变形过程模拟,分析其上拱变形的基本规律,以及砂浆层粘结强度、板边离缝深度和轨道板温度梯度对轨道板竖向上拱临界温升幅度的影响。研究结论:(1)轨道板上拱变形从板端约第一扣件处逐渐向板中蔓延,当达到某一临界温升幅度ΔT时,将导致轨道板与砂浆层的粘结失效而分离;(2)轨道板上拱临界温升幅度随着粘接强度增大而增大,增大轨道板与砂浆层的粘结强度,不仅可以抑制和延缓轨道板上拱的发生,同时可减小板边上拱程度;(3)施工过程中,采取措施减少轨道板与砂浆层的离缝面积,有利于提高轨道板上拱的临界温升幅度;(4)温度梯度的作用会加速轨道板上拱变形;(5)不同温度状态下的轨道板上拱变形现象,可反映出轨道板与砂浆层之间的不同粘结状态;(6)该研究成果对于完善CRTSⅡ型板式轨道的施工技术具有指导意义。
Abstract ： Research purposes： The slab of CRTS Ⅱ slab ballastless track lies in a state of eccentric compression during the time when the narrow gaps have been cemented and the slabs are not connected, which will easily lead to the buckling deformation for slab under the effect of temperature. A finite element model of the CRTS Ⅱ slab was established by using ANSYS software to study the buckling deformation of slab under temperature load in this paper. The weak link in the deformation process as well as the influences of bond strength of CA layer, gap depth of slab and temperature gradient of slab on the critical temperature rise amplitude of slab were analyzed by the simulation of the buckling deformation under temperature load. Research conclusions： （ 1 ） The CTRS Ⅱ track slab buckling deformation spreads gradually from the first fastener near the end point of slab to the middle of slab with the increasing of temperature. The slab may separate with the CA layer due to the bond failure under certain critical temperature AT. （2）The critical temperature increases with the increasing of bonding strength of CA layer. The larger bond strength of CA layer can not only inhibit and delay the buckling deformation, but also reduce the degree of buckling deformation. （3） The critical temperature AT increases with the decreasing of the gap area between the slab and CA layer in the construction process. （4） The buckling deformation of slab may be intensified under the effect temperature gradient of slab. （5） The bonding situation between the slab and CA layer can be reflected by the buckling deformation under different temperature. （6） The research results are useful to improve the construction technology of CRTS Ⅱ slab ballastless track.
出处
《铁道工程学报》
EI
北大核心
2015年第1期55-60,共6页
Journal of Railway Engineering Society
基金
中南大学研究生创新项目(2014ZZTS244)
中国铁路总公司科技研究开发计划课题(2013G008-E
2013G003-A-3
2014G001-D)
国家自然科学基金资助项目(U1334203
U1361204
51378513)
中南大学教师研究基金项目(2013JSJJ021)
湖南省高校创新平台开放基金项目(12K007)
