温度对系杆拱桥拱肋和系杆自振频率的影响  

Temperature effect on the natural frequency of tied arch and continuous girder bridges

作　　者：刘兴国 陶成云 黄巍 Liu Xingguo;Tao Chengyun;Huang Wei(School of civil engineering,Harbin University,Harbin 150086,China;Key Laboratory of Underground Engineering Technology of Heilongjiang Province,Harbin 150086,China)

机构地区：[1]哈尔滨学院土木建筑工程学院,黑龙江哈尔滨150086 [2]黑龙江省地下工程技术重点实验室,黑龙江哈尔滨150086

出　　处：《山西建筑》2022年第14期1-5,93,共6页Shanxi Architecture

基　　金：黑龙江省自然科学基金联合引导项目(编号:LH2019E070);寒区桥梁结构温度模式研究(编号:HUDF2017202)。

摘　　要：依据现场试验结果拟合了系杆拱桥中拱肋及系杆温度梯度模式,研究了温度变化所引起结构自振频率的变化规律及程度,并用LM-BP神经网络算法对自振频率进行了预测及验证。结果表明,温度变化对自振频率的影响随振动阶数的增加逐渐变小,且两者呈负相关关系,两者的变化量近似呈线性关系;在[-30℃,30℃]范围内的整体温度对结构频率影响最大变化率达13.56%,而拱梁温差及竖向温度梯度的影响则小得多,所以设计中应考虑整体温度的影响;该文采用的LM-BP神经网络算法对结构自振频率预测,具有一定准确度。Based on field test results,in this paper,the temperature gradient modes of arch ribs and tied bars of tied arch and continuous girder bridges were fitted.Combined with model analysis,the natural frequency variation law of structure caused by the temperature change was studied.LM-BP neural network was used to predict the natural frequency,which has been verified.The results show that the influence of temperature change on natural frequency decreases with the increase of vibration order,and the correlation between them is negative.The maximum rate of structure frequency change affected by global temperature in a range of-30℃to 30℃is 13.56%,while the rate caused by the effect of arch-beam temperature difference and vertical temperature gradient is much smaller,so the effect of global temperature should be taken into consideration when designing.This article USES the LM-BP neural network algorithm of structural natural vibration frequency is forecasted,and has a certain accuracy.

关 键 词：系杆拱桥 温度影响 自振频率 有限元分析 

分 类 号：U448.222[建筑科学—桥梁与隧道工程]