LP钢板一字内芯防屈曲支撑设计方法与抗震性能研究

发布时间：2018-02-27 16:35

本文关键词： LP钢板防屈曲支撑消能减震疲劳性能最大接触力　出处：《哈尔滨工业大学》2017年硕士论文　论文类型：学位论文

【摘要】：防屈曲支撑自提出以来便受到了国内外大量研究学者的广泛关注。传统的一字内芯防屈曲支撑,其耗能内芯通常由加强段、过渡段和屈曲段三部分组成。为了保证内芯屈曲段能够进入全截面屈服,通常在内芯加强段和过渡段焊接加劲肋以此来保证对内芯端部的约束。但是,焊接加劲肋不可避免的对内芯的疲劳性能产生不利影响,使得防屈曲支撑在焊缝处发生断裂。同时焊接的加劲肋也会引起耗能内芯的刚度突变,导致在此处产生应力集中,使得耗能内芯在此处出现局部的破坏。本文提出一种基于LP钢板(纵向变厚度钢板)的新型一字内芯防屈曲支撑。该支撑采用LP钢板作为其内芯构件。此种LP钢板一字内芯防屈曲支撑与普通支撑相比其主要优点在于它避免了在内芯屈曲段及其附近甚至在整个内芯上进行焊接,从而减小甚至消除了残余焊接应力对防屈曲支撑疲劳性能的不利影响。同时,此类新型防屈曲支撑还可以简化防屈曲支撑的制作加工工艺,且并不明显提高造价。针对此种LP钢板一字内芯防屈曲支撑,本文研究内容及相关成果如下:(1)提出了LP钢板防屈曲支撑内芯的构造设计方法,确定出其设计时应考虑的重要的控制参数。通过ABAQUS有限元软件分析了多组防屈曲支撑的力学性能,并通过仿真分析结果确定关键参数的取值范围;(2)对新型LP钢板内芯防屈曲支撑的局部稳定性能进行了分析,通过数值模拟确定了LP钢板防屈曲支撑内芯最小屈曲波长选取系数与宽厚比之间的函数关系,并发现当耗能内芯的宽厚比小于7时,研究了需要考虑耗能内芯两个方向屈曲的内芯宽厚比限值。基于以上结果,研究了LP钢板内芯局部稳定性设计方法。(3)设计了两种不同构造形式的足尺LP钢板一字内芯防屈曲支撑,并首次对这种新型防屈曲支撑进行拟静力试验研究。拟静力试验研究结果表明,两种防屈曲支撑弹性阶段的力学性能与设计值十分接近,弹塑性阶段的滞回曲线饱满、稳定,有较好的耗能能力。试验结果验证了本文所提的基于LP钢板一字内芯防屈曲支撑用于实际工程是可行性。基于以上试验研究结果,本文还并给出了端部加劲肋和内芯构件变宽度部位的设计建议。
[Abstract]:Since it was put forward, anti-buckling braces have attracted extensive attention from a large number of researchers at home and abroad. In order to ensure that the inner core buckling section can enter the full section yield, the stiffening rib is usually welded in the inner core strengthening section and the transition section to ensure the inner core end restraint. However, in order to ensure that the inner core buckling section can enter the full section yield, the transition section and the buckling section are composed of three parts. Welding stiffeners inevitably have a negative effect on the fatigue properties of the inner core, which makes the buckle-proof bracing break at the weld seam. At the same time, the welded stiffeners will also cause the sudden change of the stiffness of the energy-dissipation inner core, which will lead to stress concentration here. In this paper, a new type of inner core buckling bracing based on LP steel plate (longitudinal variable thickness plate) is proposed. LP steel plate is used as the inner core member of the bracing. This type of LP steel is used as the core member. The main advantage of plate inner core buckling bracing compared with common bracing is that it avoids welding in and around the inner core buckling section and even on the whole inner core. Thus, the negative effect of residual welding stress on the fatigue properties of buckling braces is reduced or even eliminated. Meanwhile, this new type of anti-buckling brace can also simplify the manufacturing process of buckle-resistant braces. In view of this kind of LP steel plate inner core anti-buckling support, the research contents and related results are as follows: 1) the structural design method of LP steel plate anti-buckling bracing inner core is put forward. The important control parameters that should be considered in the design are determined. The mechanical properties of multi-group buckling braces are analyzed by ABAQUS finite element software. The local stability of the new type LP steel plate inner core anti-buckling braces is analyzed through the simulation analysis results to determine the value range of the key parameters. Through the numerical simulation, the function relationship between the minimum buckling wavelength selection coefficient and the ratio of width to thickness of the inner core of buckle-resistant bracing of LP steel plate is determined, and it is found that when the ratio of width to thickness of the inner core of energy dissipation is less than 7:00, Based on the above results, the width to thickness ratio of the inner core, which needs to be considered in both directions of buckling of the inner core, is studied. This paper studies the design method of local stability of inner core of LP steel plate. The pseudostatic test results show that the mechanical properties of the two kinds of anti-buckling braces are very close to the designed values, and the hysteretic curves of the elastic-plastic stage are full and stable. The experimental results verify the feasibility of the inner core buckling bracing based on LP steel plate proposed in this paper for practical engineering. Based on the above experimental results, The design suggestions of the end stiffening rib and the variable width part of the inner core member are also given in this paper.
【学位授予单位】：哈尔滨工业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TU352.11

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