摘要
部分地锚斜拉桥是斜拉桥中的一种新体系,基于斜拉索面连续化假定研究部分地锚斜拉桥自振频率的近似计算公式.在成桥状态下,考虑斜拉索轴向刚度的垂度效应,建立了基于索面连续假定的部分地锚斜拉桥竖向正对称振动的动力平衡微分方程组.求得了部分地锚斜拉桥竖弯一阶自振频率的近似解,该近似解同样适用于自锚式斜拉桥.为验证本文计算公式的正确性,对不同跨径的钢主梁部分地锚斜拉桥和自锚式斜拉桥进行有限元建模分析,并将本文计算结果和有限元计算结果进行了对比,结果表明本文近似计算结果与有限元结果的相对误差均在5%以内.本文导出的近似计算公式可用于部分地锚斜拉桥和自锚式斜拉桥的参数分析和概念设计,也可用于验证其他数值计算方法的正确性.
Partially earth-anchored cable-stayed bridge is a new system of cable-stayed bridges. In this paper the approximate calculation formulation of nature frequency of partially earth-anchored cable-stayed bridges was studied. The dynamical equilibrium equations governing free symmetric vertical vibrations of the bridges were established based on continuous model considering the oscillations from the starting equilibrium configuration corresponding to the dead load action and sag effect of cable The approximate solution of nature frequency which is also suitable for self-anchored cable-stayed bridges was obtained. To validate the accuracy of the approximate formulas, the partially earth-anchored cable-stayed bridges and the self-anchored cable-stayed bridges with different main span by using the finite element method and the present method were calculated. Results show that the approximate calculation results have a good agreement with those of finite element models and the errors are less than 5%. The approximate calculation formulation of nature frequency of partially earth-anchored cable-stayed bridges can be applied in parameter study, conceptual design and the verification of other numerical method.
出处
《力学季刊》
CSCD
北大核心
2013年第4期650-655,共6页
Chinese Quarterly of Mechanics
基金
国家自然科学基金青年科学基金(51008223)
关键词
部分地锚
斜拉桥
连续化模型
近似法
自振频率
partially earth-anchor
cable-stayed bridge
continuous model
approximate method
nature frequency
