一种适用于宽频激励的地铁构架载荷识别方法  

A Method of Metro Bogie Frame Load Identification for Broadband Excitations

作　　者：吴养民 任尊松[1] 杨广雪[1] 金新灿[1] 徐宁[1] 杨超[1] WU Yangmin;REN Zunsong;YANG Guangxue;JIN Xincan;XU Ning;YANG Chao(School of Mechanical,Electronic and Control Engineering,Beijing Jiaotong University,Beijing,100044)

机构地区：[1]北京交通大学机械与电子控制工程学院,北京100044

出　　处：《中国机械工程》2025年第3期536-545,共10页China Mechanical Engineering

基　　金：国家自然科学基金(U2368215,52205085);中央高校基本科研业务费专项资金(2022JBXT004)。

摘　　要：工程结构动载荷识别采用传递矩阵求逆的方法将产生误差,采用载荷解耦标定方法对角化传递矩阵可避免传递矩阵求逆带来的误差。为此,基于应变测量原理研制了高精度测力构架且其测量误差低于5%,建立了地铁构架多源载荷解耦识别方法。针对地铁构架受轮轨激励影响导致载荷频带较宽从而引起激励频率接近构架弹性模态频率发生谐振的问题,通过二阶有阻尼系统在频域上直接量化谐振频率附近载荷幅值放大效应;利用最小二乘复频域法进行工作模态分析识别阻尼比;采用半功率带宽法确定谐振范围并得到校准临界频率;量化了载荷幅值放大效应并得到了载荷优化因子;基于谐振区振动加速度响应在一定程度上反映了处理后载荷的有效性。在时域、频域、损伤等方面,载荷预测应力与实测应力接近,预测损伤与实际损伤比值总体介于1.0~1.6之间,满足构架疲劳评估要求。研究结果对掌握地铁构架真实载荷特征及探讨共振疲劳问题具有重要的工程意义。The inversion of transfer matrix in dynamic load identification of engineering structures would produce errors.The load decoupling calibration method was used to diagonalize the transfer matrix to avoid errors caused by the inversion of transfer matrix.Thus,a high-precision force measurement frame with a measurement error of less than 5%was developed based on strain measurement principle,and a multi-source load decoupling identification method for metro bogie frames was established.Aiming at the problems that the frames were affected by wheel-rail excitation,resulting in a wide load band,causing resonance when the excitation frequency was close to elastic modal frequency of the frames,the load amplitude amplification effect near the resonance frequency was directly quantified in frequency domain through a second-order damping system,and the damping ratio was identified by least squares complex frequency domain method.The resonance range was determined by half-power bandwidth method and the calibration critical frequency was obtained.The load amplitude amplification effect was quantified and the load optimization factor was obtained.The effectiveness of the processed load was reflected to a certain extent based on vibration acceleration responses in resonance areas.In terms of time domain,frequency domain and damage,the load prediction stresses are close to the measured ones,and the ratio of predicted damage to actual damage is generally between 1.0 and 1.6,which meets the requirements of frame fatigue assessment.The results have important engineering significance for understanding the real load characteristics of metro bogie frames and exploring resonance fatigue problems.

关 键 词：地铁构架 载荷识别 阻尼比 谐振范围 疲劳评估 

分 类 号：U270[机械工程—车辆工程]