共查询到18条相似文献,搜索用时 62 毫秒
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本文利用虚功原理,基于修正的拉格朗日列式,得到桅杆结构增量形式的非线性有限元动力方程。在此基础上,以地震波为激励,计算了桅杆结构受地震作用的非线性位移、加速度动力响应,并对桅杆结构在纤绳初应力变化下的抗震性能进行了分析。 相似文献
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桅杆结构是一种具有较强几何非线性的结构,风荷载是其主要设计荷载。在对广义脉动风荷载样本模拟的基础上,采用增量形式的非线性有限元模型对桅杆的动力响应进行分析,并进行算例计算,说明提出的方法具有较好的精度。 相似文献
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桅杆结构的风振疲劳分析 总被引:5,自引:0,他引:5
本文提出了对桅杆结构进行疲劳风振分析的一种方法;借助于桅杆所在地的风速资料,利用接近于实际的风模拟荷载,对桅杆结构进行时域内的非线性分析,从而得到了风载下桅杆结构易破坏处应力的时程曲线。通过雨流点数计算方法,可得到不同风速下、不同应力水平下的结构年实际循环次数,并可确定结构在已使用时间内不同应力水平下的实际循环次数,结合结构疲劳P—S—N曲线及Miner线性累积损伤理论,可对桅杆进行剩余寿命估计。 相似文献
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桅杆结构动力特性分析及试验研究 总被引:2,自引:0,他引:2
通过对桅杆结构中纤绳及杆身的非线性分析,建立了桅杆结构空间自由振动方程,应用子空间迭代法可求得任意个低阶振型和频率。对不同风向及不同纤绳初拉力下桅杆结构的动力特性进行分析,与试验研究比较表明,理论计算结果与试验结果吻合良好。 相似文献
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采用了两种方法对桅杆结构进行疲劳分析;时域法和频域法;通过算例运用断裂力学方法估算疲劳寿命,经过计算与分析,得出了一些有益的结论,希望能为进一步的研究提供参考。 相似文献
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本语文基于随机振动理论对实测的桅杆结构风洞试验数据进行处理,分析了桅杆结构风振响应的频谱特性的并且从频域着手通过简单的数值运算求得足够精确的等效应力用于计算桅杆结构的风振疲劳寿命,避免了雨流点法极大的工作量。 相似文献
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本文通过对桅杆结构中纤绳及杆身的非线性分析,建立了桅杆结构空间自由振动方程,应用子空间迭代法可求得任意个低阶振型和频率。对不同风向及不同纤绳初拉力下桅杆结构的动力特性进行分析,与试验研究比较表明,理论计算结果与试验结果吻合良好。 相似文献
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三方纤绳桅杆在不同方向的风载作用下所产生的风效应是不同的.前苏联的Г.А.萨维茨基曾得出风向与纤绳平面夹角为60°时的杆身节点位移要比0°时大一倍的结论.因此,在工程设计中,杆身内力和纤绳拉力由0°风向控制,节点水平位移计算则取60°风向.本文通过桅杆结构矩阵位移法的计算实例,表明水平位移也是由0°风向控制.从而纠正了过去三方纤绳桅杆的最大位移的作用风向,简化了计算程序,保证了桅杆结构的可靠性.纠正后的三方纤绳桅杆定型设计,经过近30年的国内外大量工程实践,证明是安全、正确的. 相似文献
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He Yan-li Ma XingWang Zhao-min 《Journal of Wind Engineering & Industrial Aerodynamics》2003,91(4):513-525
Based on the idea of the discrete analysis method of random vibration, the paper studied the wind-induced response of guyed masts, the Gaussian close assumption is adopted to close the mean square equations when taking into account the nonlinearity of cables. The wind load is generated from spatially correlated filtered white noise. The discrete random vibration method can calculate accurate mean and mean square responses, the wind responses analysis for a numerical example demonstrate this point, and the results of discrete random vibration method is close to the results of experiment through wind-induced response analysis of a wind tunnel experiment model. 相似文献
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Dynamic response of guyed masts 总被引:8,自引:0,他引:8
Murty K.S. Madugula Yohanna M.F. Wahba Gerard R. Monforton 《Engineering Structures》1998,20(12):1097-1101
Natural frequencies of guyed masts were determined by modelling the mast as truss elements in one model and as beam-column elements in another model. Guys were modelled as cable elements in both cases. The natural frequencies from the two models agreed closely with each other. For the purpose of verification of the finite element modelling, two triangular steel latticed scale-modelled guyed masts were fabricated and tested on a shake table specially designed to test guyed masts. The experimental results were in good agreement with the results from the finite element analysis. The finite element modelling was then applied to six existing towers which are representative of the design practices in Canada. Based on the results of these analyses, the influence of ice accretion, guy initial tensions and torsion resistors on the dynamic characteristics of the guyed masts is discussed. 相似文献
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Monika Matuszkiewicz 《Engineering Structures》2011,33(6):2044-2048
Selected problems concerning designing of guyed masts with lattice shaft in accordance with the “EN 1993-3-1: Design of steel structures. Part 3-1: Towers, masts and chimneys-Towers and masts” European standard have been described in this paper. The method of application of the mast shaft geometrical imperfections in calculations has been discussed. Based on the performed comparative analysis of a certain mast, the influence of such imperfections on the ultimate values of internal forces in the mast shaft has been demonstrated. 相似文献
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