摘要
近区爆破引起的连续梁桥产生振动,评估爆破震动对桥梁产生的影响,为桥梁的抗爆设计提供参考依据。基于小波变换方法,采用db8小波基对振动测试信号进行分解与重构,计算爆破震动在各个频带的能量分布。以厦漳跨海大桥南汉南引桥施工期爆破监测项目为依托,建立桥梁的空间动力分析模型并进行模态分析,计算桥梁的前10阶自振频率。对23次爆破振动信号进行小波分析,结果表明,爆破振动信号的主震频带在15.625—62.5Hz内,桥梁的前9阶固有自振频率所在频带能量小于总能量的5%。
Near blasting cause the vibration of continuous beam bridge. The influence of explosion vibration on the bridge was evaluated which was helpful for the anti-explosion design of bridge. The vibration original signal was decomposed and reconstructed by the db8 wavelet basis based on the wavelet transform method. And the energy distribution of blasting vibra- tion in each band was calculated. Based on the blast monitoring project under construction for South Branch Approach Bridge of Xia-Zbang Sea-Crossing Bridge, the space dynamic model of bridge was established and the modal was also ana- lyzed to calculate the 10th natural frequency. Signals related total 23 blasting were all processed by wavelet analysis. The re- suits show that the main shock frequency band of the blasting vibration signal is in 15. 625-62.5Hz, and the energy propor- tion in the first 9th natural vibration frequency band of the bridge is less than 5% of the overall energy.
出处
《重庆交通大学学报(自然科学版)》
CAS
北大核心
2014年第1期25-27,84,共4页
Journal of Chongqing Jiaotong University(Natural Science)
基金
国家重点基础研究发展计划基金项目(2012CB723807)
关键词
近区爆破
连续梁桥
小波变换
频带能量
near blasting
continuous beam bridge
wavelet transform
frequency band energy