基于曲率模态法识别轨道板的伤损研究

无砟轨道轨道板在施工和运营中存在空洞及裂缝等伤损,伤损的出现会改变结构的动力学特性,由模态分析理论可知,系统特性的改变必然会引起模态参数的改变。建立轨道板-砂浆有限元模型,通过单元刚度的折减来模拟轨道板单处伤损和多处伤损,运用曲率模态识别伤损的方法对轨道板横向和纵向分别进行曲率模态计算分析。计算结果表明:轨道板横向和纵向任一方向的曲率模态和曲率模态差都能准确的识别出伤损位置,并且可以依据这两个指标识别出轨道板的多处伤损。

Study on Damage Identification of Track Slab Based on the Curvature Modal

Hollows and cracks develop in ballastless track slab during construction and operation. The occurrence of the damages will change the system dynamic characteristic. The modal analysis theory shows the change of the system characteristics will inevitably change the modal parameters. This paper illustrates the process to establish the finite element model of track slab-mortar,and to simulate single damage and multi damages of track slab by means of stiffness reduction of element. The calculation and analysis of curvature modal in transverse or longitudinal direction of track slab is conducted with the method of curvature modal damage identification. The results show that the curvature modal and curvature modal difference in either transverse or longitudinal direction of track slab can locate a single damage and multiple damages of track slab can also be identified.