1.华东交通大学;2.中南大学
国家自然科学基金项目(52078487)，轨道交通基础设施性能监测与保障国家重点实验室项目(HJGZ20212003, HJGZ20212009)
National Natural Science Foundation of China(52078487), Project of State Key Laboratory of Performance Monitoring and Guarantee of Rail Transit Infrastructure(HJGZ20212003, HJGZ20212009)
基于前期开发的高速铁路基础变形诱发轨道结构变形与层间接触性状演变的通用表征模型，植入余弦型路基沉降描述函数，引入用以刻画轨道-路基间接触非线性的Heaviside函数，推导余弦型路基沉降下纵连板式无砟轨道各层结构的变形方程，利用渐进性接近法求解含接触非线性的超静定方程，进而分析余弦型路基沉降对轨道各层结构变形和层间接触性状演变的影响规律。结果表明:在余弦型路基沉降区域内，轨道随路基沉降发生“跟随性”变形，当路基沉降波长一定时，轨道下沉和上拱均随路基沉降幅值的增加而增大，当沉降幅值一定时，轨道下沉随路基沉降波长的增加而增大，但上拱却减小；轨道-路基间的脱空区域及轨道的受力曲线呈左右对称，轨道整体刚度影响脱空长度和高度；当路基沉降波长为10m时，随路基沉降幅值的增加，脱空高度和长度增长的同时，还会整体向远离沉降区方向“平移”；当路基沉降幅值为10mm时，需要重点关注沉降波长小于20m的不均匀沉降。
Based on the pre-development general characterization model of track structure deformation and the evolution of interlayer interface state induced by the deformation of high-speed railway foundation, the description function of cosine subgrade settlement was implanted, and the Heaviside function was introduced to describe the contact nonlinearity between track and subgrade, the deformation equation of each layer of longitudinally connected ballastless track under cosine subgrade settlement was derived, the progressive approximation method was used to solve hyperstatic equation with contact nonlinearity, and the influence law of cosine subgrade settlement on the track structure deformation of each layer and the evolution of interlayer interface state was analyzed. Results indicate that: in the cosine subgrade settlement area, the track deforms accordingly with the subgrade settlement, when the subgrade settlement wavelength is constant, the track settlement and heaving increase with the increase of the subgrade settlement amplitude, when the settlement amplitude is constant, the track settlement increases with the increase of the subgrade settlement wavelength, but the track heaving decreases. The void area between track-subgrade and the track force curve are symmetrical, and the track overall stiffness affects the void length and height. When the subgrade settlement wavelength is 10m, with the increase of the subgrade settlement amplitude, the void height and length increase, it will also shift away from the settlement area as a whole. When the subgrade settlement amplitude is 10mm, it is necessary to focus on the uneven settlement with settlement wavelength less than 20m.
