摘要
CRTSⅡ型板式无砟轨道在常年反复的使用过程中,其CA砂浆层易出现层间离缝、脱空等损伤。目前应用冲击回波法对无砟轨道板进行的无损检测需要在轨道板上布置较密的测线,并进行多点激发与接收。这种方法不适合对轨道板CA砂浆层损伤进行快速普查。作者用三维有限元法分析了单点激发下应力波在CRTSⅡ型轨道板中的传播规律。通过比较有无CA砂浆层缺陷轨道板周边的速度或加速度峰值,发现可根据CA砂浆层缺陷引起的速度或加速度峰值的变化率检测缺陷。如果取6%的变化率为阀值,在轨道板周边按20cm的间距设加速度检测点,或按30cm的间距设速度检测点,单点激发即可识别CA砂浆层中40cm×40cm以上的损伤。
In the routine operation of high-speed railway,the CA mortar layer of CRTSⅡballastless track is prone to be damaged,such as the generation of layer separation and voids.At present,the nondestructive testing of ballastless track slab by impact echo method needs to arrange dense survey lines on the track slab and carry out multi-point excitation and reception.This method is not suitable for the quick survey of the damage of CA mortar layer.In this paper,the three-dimensional finite element method was used to analyze the propagation characteristics of stress wave in the CRTS II ballastless track structure under single point excitation.By comparing the peak values of velocity and acceleration around track slab with or without defects in the CA mortar layer,it is found that defects in the CA mortar layer can generate obvious changes of the peak values of velocity and acceleration.If a change rate of 6%is taken as the threshold,and velocity measuring points are set at a distance of 30 cm or acceleration measuring points are set at a distance of 20 cm,around the track slab,the damage above 40 cm times 40 cm in CA mortar layer can be identified using stress wave method by single point excitation.
作者
肖子葳
朱国甫
张杰
XIAO Zi-wei;ZHU Guo-fu;ZHANG Jie(Hubei Key Laboratory of Theory and Application of Advanced Materials Mechanics,Wuhan University of Technology,Wuhan 430070,China;Wuhan Sinorock Technology Co Ltd,Wuhan 430074,China)
出处
《武汉理工大学学报》
CAS
2021年第6期34-40,共7页
Journal of Wuhan University of Technology
基金
国家自然科学基金(11672215)。
