摘要
为研究纵连板式无砟轨道-桥梁整体的动力性能,对桥上CRTSⅡ型无砟轨道建立了多测点测量系统,详细观测了CRTSⅡ型轨道工作时各结构的响应特征,对各结构的横向加速度、竖向加速度、竖向位移以及梁体的自振频率、阻尼比、动力系数进行了统计分析.结果表明:CRTSⅡ型无砟轨道系统的竖向总减振率可达90%以上,行车振动传至桥面板时,最大竖向加速度幅值为3.93 m/s^2,最大竖向位移幅值为0.131 4 mm,满足相关规范要求;行车振动对邻线影响较小,且影响主要集中在简支梁固定支座端;车致振动响应基本与行车速度呈正相关;在特定速度附近,部分结构可能产生与轨道系统整体不同步的振动模式,存在离缝与损坏的隐患;在CRTSⅡ型无砟轨道系统下,简支梁一阶竖向自振频率约为7.27 Hz,略大于裸梁理论值.
In order to explore the dynamic performances of continuous CRTS Ⅱballastless track slab-bridge system, a multi-point measuring system was established. With the help of this system, the dynamic response of each compo-nent of the system was observed in detail, and the lateral acceleration, vertical acceleration and vertical displace-ment of the CRTS Ⅱ track slab system, as well as the natural vibration frequency, damping ratio and impact coeffi-cient of the beam, were analyzed statistically. The results show that （1） CRTS Ⅱ track slab system has a good ca-pability of buffering train-induced vibrations, with a total vibration reduction rate of more than 90% , a maximum vertical acceleration of bridge deck of 3. 93 m/s2 and a maximum vertical displacement of 0. 131 4 mm after the vi-bration has been transferred to the bridge deck, which meets the requirements of the related standards ; （2 ） the train load-induced vibration has a slight effect on the adjacent railway, which focuses on the fixed support side; （3 ） the train load-induced vibration is primarily positively related to the train speed, and parts of the structure may vibrate differently from the track slab-bridge system at a special train speed, which may lead to cracks or dam-age ;and （4） the measured one-order natural vibration frequency of simply-supported beam in the CRTS Ⅱ track slab-bridge system is about 7. 27Hz, which is slightly greater than the theoretical one of the simply-supported beam without track slab.
出处
《华南理工大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2017年第4期95-102,共8页
Journal of South China University of Technology(Natural Science Edition)
基金
国家自然科学基金资助项目(51378503)
中国铁路总公司科技研究开发计划资助项目(2015G001-K)~~
关键词
CRTS
Ⅱ型板
简支梁
无砟轨道
动力响应
自振频率
CRTS Ⅱ slab
simply-supported beam
ballastless track
dynamic response
natural vibration fre-quency
