【摘要】 双向预应力混凝土框架箱梁在国内高铁站轨道桥梁中开始得到应用,为了掌握该结构形式复杂的受力变形特性,本文介绍了一种基于光纤光栅传感技术的轨道层桥梁变形同步监测系统,通过在结构关键位置布设光纤光栅传感器,对列车进出站过程多个截面变形进行同步监测,在列车运营1年时间内共捕捉9种不同的荷载模式及其变形数据,监测结果显示,随着列车进出站,结构会出现明显的周期性变形,振幅由车厢自重与乘客重量决定,变化周期与列车车速表现为负相关,在列车进站和出站期间,结构变形有明显的对称关系;而横向主梁关键位置监测到微小的应变,说明列车荷载通过横向主梁往两端传递,但相邻轨道间影响很小。更多还原

【Abstract】 Bidirectional prestressed concrete frame box girder structure begins to be applied in track bridge of High-speed Rail station in China now. In order to master complex bearing and deforming behavior of this structure,this article introduces a synchronous deformation monitoring system of bridge track layer based on fiber Bragg grating sensing technology. By layouting fiber Bragg grating sensors on key positions of the structure,a synchronous deformation monitoring on multiply sections is realized when train pulls in and departs the station. Nine different load patterns and deformation data are captured in the train operation period within 1 year,the monitoring results show,the obvious periodic deformation appears on structure when train pulls in and departs the station,its amplitude is determined by the self weight of carriage and weight of passengers, periodicity and train speed show negative correlation, structure deformation is also obviously symmetrical during the two periods. Small strain is monitored on the key positions of transverse girder,this shows that the train load transfers to both ends of this girder,but the impact is very small between adjacent tracks of the structure.更多还原