车桥随机振动作用下的桥梁动态影响线研究  

Dynamic Deflection Influence Lines of Bridges Subjected to Vehicle-Bridge Random Vibration

作　　者：徐文涛[1] 张建波[1] 魏星[1] 

机构地区：[1]郑州大学力学与工程科学学院,郑州450001

出　　处：《应用数学和力学》2015年第9期914-923,共10页Applied Mathematics and Mechanics

基　　金：国家自然科学基金(11402235);教育部科学技术研究重点项目(212105)~~

摘　　要：将传统的静态影响线概念推广到动态影响线范围,研究了在车辆荷载和桥面随机不平度的作用下,简支梁桥和3跨弹性支承梁桥跨中挠度的动态影响线.基于虚拟激励法将桥面不平度转化为确定性的简谐激励,并采用精细积分法对车桥系统方程求解,获得了桥梁跨中挠度动态影响线的均值和标准差.基于3σ法则构造虚拟激励输出响应的确定值计算方法,获得了桥梁挠度动态影响线的确定性值域.最后通过算例分析了桥梁动态影响线的随机特性和车速与桥面不平度等级变化对桥梁动态影响线的影响,并研究了简支梁桥和弹性支承梁桥在随机振动作用下的动态影响线差异.The concept of traditional static influence lines was extended to the dynamic field, and the dynamic deflection influence lines at the span centers of a simply-supported bridge and a 3-span elastically supported bridge were studied in view of the interaction between the bridge random deck roughness and the vehicle. To obtain the mean values and standard deviations of the dynamic influence lines at the bridge span centers, the deterministic harmonic excitations were derived from the bridge deck roughnesses with the pseudo-excitation method, and the e- quation for the vehicle-bridge system was solved with the precise integration method. Based on the 3σ method, the deterministic value ranges of the dynamic deflections were obtained. Final- ly, the random characteristics of the dynamic influence lines were analyzed through numerical examples, and the effects of vehicle velocity and bridge random deck roughness on the dynamic influence line were discussed. Then the difference of dynamic influence lines between the sim- ply-supported bridge and the 3-span elastically supported bridge was discussed.

关 键 词：桥面不平度 车桥耦合 虚拟激励法 精细积分法 动态影响线 

分 类 号：U441.2[建筑科学—桥梁与隧道工程]