立交桥曲线箱梁动力分析模型

提出了1种双脊骨空间有限元模型,用来模拟和分析立交桥曲线箱梁的固有振动特性和动力反应。将曲线箱梁分别看作是由空间梁或壳组成的空间结构,并分别采用分段空间直梁模型、壳元模型和实体元模型进行模拟,分析相同曲线箱梁的振动特性和地震时程反应,通过与双脊骨模型的计算结果的比较验证双脊骨模型的可靠性。初步研究了在相同曲率半径下不同跨度的曲线箱梁的固有振动特性,分析了双脊骨模型的脊骨间距、横向连接间距等参数对模型计算结果的影响。研究结果可为曲线梁桥抗震性能和地震反应分析提供参考。

A dynamic model of curved box girder beam in highway interchanges

In this paper,a dual-beam stick finite element model is presented to analyze the dynamic characteristics and seismic responses of a curved girder with a box section in the highway interchanges.The curved box girder is regarded as a space structure consisting of beams and shells respectively,and modeled by discrete 3-D straight beams,shell elements and solid elements.The vibration properties and earthquake time history responses of the curved box girder are analyzed and computed on the basis of these models, and the results are compared with that of the dual-beam stick model to validate the reliability of this model.The natural dynamic characteristics of the curved box girders with the same radius of circle and different curved length are studied,and the influences of the distance between two sticks and the distance between two diaphragms are also researched.This study is helpful for evaluations of dynamic characteristics and seismic capacity of the curved girder bridges.