摘要
以日照市沿海地区一新建高速铁路高架桥段为研究对象,首先通过现场试验分析振动波在桥梁结构及下部基础中的传递特性,然后建立桥墩—岩土层三维有限元模型,通过数值仿真进一步研究不同激振频率下地面竖向位移响应。结果表明:外部激励作用下列车荷载产生的中高频振动对桥梁上部结构影响显著;振动以弹性波的形式在岩土介质中衰减,主要衰减频率在15 Hz以下和83 Hz以上,其间中高频段的衰减相对较弱;与土质地层相比,岩土地层对振动的滤波作用较弱,20 m以外10~60 Hz频段地面振动响应频率成分仍然较为丰富。因此,岩土地层区段高速铁路环境振动评估不仅要考虑20 m以内中高频段的地面振动,还应该关注20 m以外的地面振动,尤其是尚未完全衰减的10~20 Hz较低频段的振动。
Taking the viaduct section of a new high speed railway in the coastal area of Rizhao City as the research object,firstly,the transmission characteristics of vibration wave in the bridge structure and lower foundation were analyzed through field test,then the three-dimensional finite element model of pier-rock soil layer was established,and the vertical displacement response of the ground under different excitation frequencies was further studied through numerical simulation.The results show that the medium and high frequency vibration caused by train load under external excitation has a significant impact on the bridge upper structure.The vibration is attenuated in geotechnical medium in the form of elastic wave,and the main attenuation frequency is below 15 Hz and above 83 Hz,during which the attenuation of medium and high frequency band is relatively weak.Compared with soil stratum,the filtering effect of soil-rock stratum on vibration is weak,and the frequency components of ground vibration response in 10~60 Hz frequency band are still rich beyond 20 m.Therefore,the environmental vibration assessment of high speed railway in soil-rock stratum area should not only consider the ground vibration in the medium and high frequency band within 20 m,but also pay attention to the ground vibration beyond 20 m,especially the vibration in the lower frequency band of 10~20 Hz that has not been fully attenuated.
作者
邢梦婷
杨飞
魏子龙
姚永明
王平
XING Mengting;YANG Fei;WEI Zilong;YAO Yongming;WANG Ping(Infrastructure Inspection Research Institute,China Academy of Railway Sciences Corporation Limited,Beijing 100081,China;Key Laboratory of High-speed Railway Engineering of Ministry of Education,Chengdu 610031,China)
出处
《铁道建筑》
北大核心
2021年第10期158-162,共5页
Railway Engineering
基金
中国铁道科学研究院集团有限公司基金(2020YJ067)。
关键词
高速铁路
环境振动
试验研究
岩土地层
弹性波
传播衰减规律
高架桥段
high speed railway
environmental vibration
experimental study
soil-rock stratum
elastic wave
propagation attenuation law
viaduct section
作者简介
第一作者:邢梦婷(1992-),女,博士。E-mail:xingmengting521@foxmail.com。
