【作者】 陶健；

【导师】 李忠学；

【作者基本信息】 浙江大学 ， 结构工程， 2011， 硕士

【摘要】 高层钢结构同时承受水平荷载与竖向荷载。竖向支撑作为高层钢结构中主要的抗侧力构件,承担了水平荷载作用产生的大部分剪力。在实际分析竖向支撑的受力时往往只考虑水平荷载的作用,而忽略竖向荷载作用产生的支撑内力。随着高层钢结构建筑的不断发展,建筑高度不断提升,结构形式也越来越复杂,在某些情况下分析竖向支撑内力时,考虑与不考虑竖向支撑承受竖向荷载的作用往往会产生较大的偏差。本文利用ansys强大的参数化设计与数据后处理功能,对结构进行模块化的建模设计,针对框架-支撑体系、框架内筒体系、筒中筒体系、成束筒体系、巨型支撑外筒体系以及巨型框架体系等六种不同的高层钢结构体系,分析了考虑与不考虑竖向支撑承受竖向荷载时其受力的计算偏差。研究了在结构设计时忽略竖向支撑承受竖向荷载作用的合理性。通过计算支撑框架只施加水平荷载与取消支撑的框架只施加竖向荷载时构件的内力迭加值,并将其与同时承受水平与竖向荷载的支撑框架的构件内力值进行对比,探讨了考虑与不考虑竖向支撑承受竖向荷载作用时对于结构其他构件受力的影响情况。分析框架-支撑体系与框架内筒体系时,考虑与不考虑竖向支撑承受竖向荷载作用,支撑的内力的偏差范围在1%-10%之间,特别是对于人字型支撑,考虑其承受竖向荷载时的影响明显小于单斜杆支撑。在筒中筒与成束筒结构的计算比较中发现,前者由于其外筒侧向刚度较大,竖向荷载在竖向支撑中所占的效应较大,而成束筒体系由于各框筒独自承担了各自的竖向荷载,考虑与不考虑支撑承受竖向荷载作用时,其轴力值的偏差范围基本上都在7%以内。通过对巨型支撑外筒体系与巨型框架体系的受力比较分析发现,巨型支撑在承担水平荷载的同时承担了大部分的竖向荷载,而后者在考虑与不考虑竖向支撑承受竖向荷载作用时其结构中下部的支撑轴力值偏差范围在20%-30%之间,因此,对这种结构体系应充分考虑到支撑内力中的竖向荷载效应。更多还原

【Abstract】 There are always two or more types of loads exposed to high-rise steel structures, such as vertical loads and horizontal loads, and the vertical bracings as the main resistance components to lateral force, are mainly responsible for the shear force produced by the horizontal loads. In the actual analysis of support forces always mainly considers the role of horizontal loads while neglecting the role of the vertical bracing system resisting to vertical loads. With the development of high-rise steel structures, buildings become higher and more complex, so in some mechanical analysis of support system, whether or not considering the role of vertical bracing to bear vertical load tends to produce much more deviations.This paper uses ANSYS with its great advantages in parametric design and data post-processing to do modular modeling design. For the six different high-rise steel structures of the framework-support system, framework-tube system, tube in tube system, frame-tube bundle system, giant outer-support system and mega-frame system, this article analyzes the deviation range of the force in vertical bracing systems with or without considering the vertical support to bear vertical load, and does the research on the rationality in structural design ignoring the braces to withstand the vertical loads. Through the superposition of internal forces produced by framework-support structures exposed to horizontal loads and net framework structures exposed to vertical loads, this paper further discusses the situation of other components in the structures with or without considering the bracing system to bear vertical loads.For the framework-support system and framework-tube system, the deviation range of forces in braces is from 1% to 10% with or without considering the bracing system to bear vertical system Forces, and the influence of the vertical loads applied to herringbone braces is significantly less than the one applied to diagonal braces. Because of the great lateral stiffness in outer tube, horizontal loads and vertical loads play equally role in terms of forces in the braces for the tube in tube system. For the frame-tube bundle system, because each frame-tube structure has a commitment to vertical loads solely, the deviation range of forces in braces is almost under 7% with or without considering the bracing system to bear vertical system. Finally, through the comparison analysis of forces in braces for giant outer-support system and mega-frame system, the former giant braces play a major role in resisting the horizontal loads while resisting most vertical loads at the same time, and the latter deviation range of forces in braces is between 20%-30% whether or not considering the effects of vertical bracing system resisting vertical loads.更多还原