冲击荷载作用下CRTSⅢ型板式轨道-路基系统动力特性研究

应用ABAQUS有限元软件建立CRTSⅢ型板式轨道-路基动力分析模型,计算了在落轴冲击荷载作用下CRTSⅢ型板式轨道-路基系统的动力响应,并将仿真计算结果与试验结果进行了对比,验证了模型的可靠性.在此基础上,研究了扣件刚度、路基基床弹性模量、自密实混凝土弹性模量以及长期服役状态下混凝土弹性模量的降低对轨道-路基系统动力特性的影响规律.结果表明:扣件刚度对各部件振动加速度影响较大,路基基床弹性模量对其影响较小;轨道结构在服役过程中混凝土弹性模量的降低会引起轨道板加速度有较大的增幅,应引起重视.

Dynamic analysis of CRTS Ⅲ slab track-subgrade system under impact load

A three-dimensional dynamic analysis model of CRTS Ⅲ slab track-subgrade is established based on the software ABAQUS. The dynamic response of the CRTS Ⅲ slab track-subgrade system under the wheel-drop impact load is obtained using the dynamic analysis model. Comparisons with experiment tests support the reliability of the model. Further, the effects of the fastener stiffness, the modulus of the subgrade bed, the modulus of the self-compacting concrete, and the modulus decrease of concrete structures during the long-term service on the dynamic characteristics of the CRTS Ⅲ slab track-subgrade system is investigated. Results show that the fastener stiffness has a significant influence on the accelerations of all the track structures, while the modulus of the subgrade bed has a negligible effect on the dynamic response of the system. Much attention should be paid to the phenomenon that the modulus decrease of track structures in the service life can cause a notable increase in the acceleration of the track slab.