【作者】 王佳伟；

【导师】 贾艳敏；

【作者基本信息】 东北林业大学 ， 桥梁与隧道工程， 2008， 硕士

【摘要】 预应力的存在对结构的静力和动力特性均会产生影响。预应力对结构的静力效应已经有了比较合理的定论。除了研究预应力结构的静力效应外,很有必要研究预应力对结构动力特性的影响。文章阐述了预应力钢结构国内外发展现状和预应力结构振动问题国内外研究现状;介绍了普通简支梁自振频率计算公式和预应力钢索为直线形、单折线形和双折线形布置的预应力简支梁自振频率计算公式;推导了预应力钢索为曲线形布置的预应力简支梁自振频率计算公式。文章结合哈尔滨市工农兵钢箱梁桥试验模型结构特点,应用有限元分析软件ANSYS建立了普通简支钢箱梁和预应力简支钢箱梁模型并对其进行模态分析;应用普通简支梁自振频率计算公式和文章推导的自振频率计算公式对无索状态和有索状态的试验模型进行计算。将自振频率理论计算结果、有限元计算结果和模型试验测试结果进行对比分析,从而验证了本文自振频率计算公式推导和有限元模型的正确性。文章采用有限元法分析了预应力对普通简支钢箱梁振动特性的影响;采用有限元和理论计算相结合的方法分析了预应力钢索索力、钢索截面面积、钢索锚固位置和钢索布置方式对预应力简支钢箱梁振动特性的影响。更多还原

【Abstract】 The existence of prestress can not only influence the static effects of structures but also the dynamic effects of structures. The influence of prestress on static effects of structures already had reasonable conclusion. It is necessary to study the influence of prestress on dynamic behavior of structures except static effects of prestressed structures.This paper elaborated domestic and foreign development status of prestressed steel structures and study status of vibration issues of prestressed structures. Then the paper introduced free vibration frequency formula of simply supported beam and simply supported beam with linear prestressed tendons, single broken line prestressed tendons and double broken line prestressed tendons and deduced free vibration frequency formula of simply supported beam with curved prestressed tendons.Combined with text model structure characteristics of Harbin Gongnongbing steel box girder, models of simply supported steel box girder and simply supported steel box girder with prestressed tendons were established by means of finite element analysis software ANSYS and carried on mode analysis to them. The free vibration frequency of text model without prestressed tendons and text model with prestressed tendons were calculated by free vibration frequency calculation formula of simply supported beam and simply supported beam with prestressed tendons. The free vibration frequency formula which this paper deduced and the finite element models were verified well by comparing free vibration frequency results of theoretical calculation, finite element analysis and model text.The influence of prestress on vibration behavior of simply supported steel box girder were analyzed by finite element method. And then the article analyzed the influence of the prestress value in cables, the cable sectional area, the cable anchor position and the cable layouts on vibration behavior of simply supported steel box girder with prestressed tendons by finite element and theoretical calculation method.更多还原