摘要
利用修正的Timoshenko梁振动理论建立了等截面斜桥振动频率的超越方程和静力、动力分析有限元列式,用解析法和有限元法分析了斜度、支承方式对单跨斜桥结构前5阶振动频率的影响,对单跨斜桥车-桥振动进行了分析,考察了车速对动挠度、动弯矩的影响和不同截面振动的同相性及最大动挠度、最大动弯矩发生的部位,比较了不同车速条件下规范方法、车-桥振动方法计算的挠度、弯矩冲击系数的差别。算例结果表明:斜桥自振频率解析解与有限元解一致、斜度和支承方式对斜桥动力特性有重要影响、车辆的冲击效应与车速没有单调变化规律、挠度和弯矩的冲击系数不同。
Modified Timoshenko beam theory was used to establish the transcendent equation of vibrating frequency and finite element formulations for static and dynamic analysis.The first five order frequencies were obtained by analytic method and finite element method,which depend on obliquity and supporting manners.The interaction of vehicle-bridge system for single span skewed bridge was studied,and the vehicle velocity was found to affect the dynamic deflection and dynamic moment,synchronization of different cross-section,and the positions of maximum dynamic deflection and dynamic moment.Impact factors of deflection and moment calculated by bridge specification method and vehicle-bridge system method for different vehicle velocities were compared,indicating that（1） theoretic vibrating frequencies are consistent with finite element results for skewed bridge,（2） obliquity and supporting manner have significant influences on dynamic characteristics,（3） the impact effect and velocity of vehicles do not change monotonously,and（4） the impact factors of deflection and moment are different for skewed bridge.
出处
《工程力学》
EI
CSCD
北大核心
2010年第3期30-37,共8页
Engineering Mechanics
基金
国家自然科学基金项目(50778024)
中国博士后基金项目(20080441177)
关键词
斜桥
振动频率
车-桥振动
冲击效应
理论公式
有限元
skewed bridge
vibrating frequency
vehicle-bridge vibration
impact effect
theoretic formula
finite element
