【摘要】 为了研究高墩连续刚构桥基频函数表达式,以某一典型桥梁为例,构造了多种不同的桥梁结构形式,建立了64种有限元分析模型,获取了桥梁结构自振特性规律,并提出了桥梁纵向振动的基本振型函数;在此基础上利用瑞利法推导了高墩连续刚构桥纵向振动基频的理论计算公式,最后对此公式的可行性进行了算例验证,讨论了现有抗震规范在此类桥梁结构基频计算上的适用性。结果表明:高墩连续刚构桥第一阶振动以桥墩的纵向振动为主;给出的由能量法得到的基频计算值与有限元模型计算值误差为5%;抗震设计细则中的自振频率计算公式不适用于高墩刚构桥此类非规则桥梁。更多还原

【Abstract】 In order to obtain the function of fundamental vibration frequency of the rigid frame bridge,firstly,a typical rigid frame bridge with high piers was taken as an example,and 64 similar bridges were fabricated and their finite element(FE) models were set up to obtain the structural natural vibration characteristics,then,the fundamental mode shape function of this type of structure was put forward so as to deduce the theoretical fundamental frequency formula by Rayleigh method.Finally,the presented theoretical formula of fundamental frequency was validated by the engineering and the fundamental frequency formula in the current guidelines for seismic design of highway bridges was discussed therein.The results indicate that the basic oscillation of the rigid frame bridge with high piers consists of the longitudinal vibration of piers,and that the fundamental frequency calculated by the recommended method has an error of 5% compared with the FE result,and the frequency calculation in the guidelines can not be applied to such irregular bridges as the rigid frame bridges.2 tabs,2 figs,15 refs.更多还原