摘要
基于在建包银高铁桥梁的地震响应实测数据,通过快速傅里叶变换(FFT)对桥梁结构的加速度响应信号进行时域峰值和PGA放大系数分析,并提取地震响应信号在不同频段范围内的子信号,揭示地震作用下桥梁在各频段的响应分布特征。研究表明,(1)地震作用下在建桥梁仅在桥梁悬臂端ZA1、ZA2测点出现较为显著的P波与S波分界特征,其余测点此特征不显著,甚至未出现。(2)地震波在桥梁结构的传递过程中,ZA3至ZA1的PGA放大系数呈线性增长趋势,ZA1测点达到11.062;ZA3至ZA5的PGA放大系数则表现出先放大后逐渐减小的趋势,ZA3测点为1.555。(3)在建桥梁结构的阻尼和耗散效应显著抑制f2(9~13 Hz)、f3(22~26 Hz)中高频段成分的响应,而在与结构固有频率接近的f1(1~5 Hz)低频段成分中,尤其在桥梁的悬臂端,表现出较好的传递特性,表明桥梁悬臂施工阶段的抗震防护尤为重要。
Based on the seismic response data of the under-construction Baotou-Yinchuan High-speed Railway bridge,Fast Fourier Transform(FFT)was used to analyze the time-domain peak values and PGA amplification factors of the bridges structural acceleration response signals.Additionally,sub-signals in different frequency bands of the seismic response were extracted to reveal the response distribution characteristics of the bridge in each frequency band under seismic effects.The results of the study show that:(1)under seismic effects,significant P-wave and S-wave boundary features are observed only at the cantilever ends of the bridge(measurement points ZA1 and ZA2),while these features are not significant or even absent at other measurement points.(2)During the transmission of seismic waves through the bridge structure,the PGA amplification factor from ZA3 to ZA1 shows a linear increasing trend,reaching 11.062 at ZA1,while the PGA amplification factor from ZA3 to ZA5 exhibits an initial increase followed by a gradual decrease,with ZA3 showing a value of 1.555.(3)The damping and energy dissipation effects of the under-construction bridge structure significantly suppress the high-frequency response components in the f2(9-13 Hz)and f3(22-26 Hz)frequency bands.However,in the low-frequency components near the bridges inherent frequency,particularly in the f1(1-5 Hz)band,the transmission characteristics are notably better,especially at the cantilever ends of the bridge.The results indicate that seismic protection during the cantilever construction phase of the bridge is particularly crucial.
作者
钟海江
刘旭
朱红兴
祝克栋
王辉
郑德传
赵守全
ZHONG Haijiang;LIU Xu;ZHU Hongxing;ZHU Kedong;WANG Hui;ZHENG Dechuan;ZHAO Shouquan(China Railway Beijing Engineering Bureau Group Sixth Engineering Co.,Ltd.,Shenyang 110136,China;China Northwest Research Institute Co.,Ltd.of CREC,Lanzhou 730070,China)
出处
《铁道勘察》
2025年第4期141-146,共6页
Railway Investigation and Surveying
基金
甘肃省青年科技基金项目(23JRRA1364)
中铁北京工程局集团有限公司科技开发项目(包银-研2021)。
关键词
高速铁路
转体桥
地震作用
动力响应
加速度
频谱特性
high-speed railway
swivel bridge
seismic action
dynamic response
acceleration
spectral characteristics
