摘要
以变速移动荷载模拟车辆变速过桥,建立车轮加弹簧—阻尼器—簧上质量和均布质量2种变速移动荷载下欧拉梁的动力分析模型,并推导其运动控制方程。运用数值分析,研究简支梁在不同上桥初速度和加速度的匀变速移动荷载作用下的动力响应。结果表明:荷载以不同的加速度变速过桥时,桥梁的跨中挠度时程和动力放大系数曲线与匀速过桥时相似;变速移动荷载对桥梁动力响应的影响与荷载上桥初速度、加速度以及桥梁跨度等因素有关;移动车辆荷载使梁发生极大动力响应的上桥初速度出现在若干速度点上,是不连续的;跨中挠度不随移动荷载加速度的变化单调变化;简支梁跨度越大,变速移动荷载对跨中挠度的影响越大。
By simulating vehicles moving on bridge with varying speeds, the dynamic analysis model of a simply-supported beam under two speed-varying loads, a wheel-spring-damper-spring mass load and a uni- formly-distributed mass load, is established, and their motion equations are derived. The dynamic responses of the simply-supported beam under the action of speed-uniformly varying loads with different initial speeds and accelerations are studied by computer simulation. The calculation results show that the defection curves and the dynamic factors of the beam under loads with different accelerations are similar to those when the loads move with constant speeds. The speed-varying load affects the dynamic responses of the beam through the entrance speed and acceleration of the load, the span of the bridge, etc. The entrance speeds of the load which induce maximum responses of the beam are discontinuous and appear as several speed points. The beam deflection is not monotone changing with the load acceleration. The influence of speed-varying load on the beam deflection increases with the beam span length.
出处
《中国铁道科学》
EI
CAS
CSCD
北大核心
2007年第6期41-46,共6页
China Railway Science
基金
国家自然科学基金资助项目(50538010)
关键词
简支梁
变速移动荷载
动力系数
变速效应系数
Simply-supported beam
Speed-varying load
Dynamic factor
Speed-varying coefficient
