不同分隔比的分体柱受力性能试验研究

发布时间：2018-07-01 09:01

本文选题：分体柱 + 分隔比　；参考：《烟台大学》2017年硕士论文

【摘要】：柱作为框架结构的竖向承重构件和抗水平侧移构件,在结构的抗倒塌中起着非常关键的作用。在高层框架结构或框剪结构底部、转换层以及楼梯间等位置,因轴压比和层高的限制,多会形成剪跨比较小的短柱。历次地震灾害调查表明短柱刚度较大,变形能力较差,地震中多发生脆性破坏。已有研究提出了分体柱技术,即通过在柱体内设置十字交叉的隔板,将柱体分割为4个独立单元柱,在保证柱体轴压比不变的同时,将柱体剪跨比增加一倍。分体柱技术使短柱的破坏形态由整体柱的脆性剪切破坏发展为单元柱的压弯破坏,改变了短柱的破坏模式。本文在分体柱研究的基础上针对目前分体柱的相关研究中,隔板宽度与柱截面宽度相同,导致柱体在地震或破坏过程中,在较小荷载时沿隔板出现竖向裂缝,导致单元柱间相对变形,承载力降低;而隔板尺寸变化与柱截面尺寸的关系对短柱受力性能的影响也未见相关研究,因此,本文设计了3个不同分隔比(隔板宽度与柱体截面的比值)的分体柱试件,通过进行恒定轴力作用下的拟静力试验,研究分隔比变化对分体柱受力性能的影响,研究成果为:(1)完成了3个不同分隔比分体柱试件在恒定轴力作用下的拟静力试验,得到了分体柱试件的破坏形态和破坏模式,结果表明:分隔比变化对分体柱的破坏过程和破坏模式影响较小,即不同分隔比的分体柱均发生压弯破坏。(2)本文通过试验得到了柱体破坏的具体数值,分析了各分体柱的滞回曲线、骨架曲线、承载能力、变形能力、刚度变化、钢筋应变等性能指标,研究结果表明:随着分隔比的减小,分体柱的峰值承载力提高、延性降低、耗能能力减弱、刚度退化速率加快,表明分隔比是影响分体柱受力性能的重要因素。(3)运用有限元ABAQUS软件建立了3个不同分隔比的分体柱模型,对各分体柱模型进行模拟计算,明晰了分隔比变化对分体柱的破坏模式、骨架曲线和承载力等指标的影响,对比试验和模拟数据验证了模型的准确性和合理性。
[Abstract]:Columns, as vertical load-bearing members and lateral displacement resistant members of frame structures, play a very important role in the collapse resistance of structures. At the bottom of the frame structure or the frame shear structure, the transition floor and the staircase, the short columns with small shear span will be formed because of the limit of axial compression ratio and story height. The investigation of previous earthquake disasters shows that the short columns have large stiffness, poor deformation capacity and brittle failure in earthquakes. The split-column technique has been put forward, that is, the column is divided into four independent columns by setting a cross-section in the column. The column shear span ratio is doubled while the axial compression ratio of the column is not changed. The failure mode of short columns is changed from brittle shear failure of integral columns to compression and bending failure of element columns, which changes the failure mode of short columns. In this paper, based on the research of split columns, the width of the diaphragm is the same as the width of the section of the column, which leads to vertical cracks along the diaphragm in the process of earthquake or failure, when the load is small. As a result of the relative deformation between the elements and the reduction of the bearing capacity, the relationship between the size change of the diaphragm and the section size of the column has not been studied on the behavior of the short column. In this paper, three split-column specimens with different separation ratios (the ratio of the diaphragm width to the column section) are designed. The influence of the variation of the separation ratio on the mechanical properties of the split column is studied by the quasi-static test under the constant axial force. The results are as follows: (1) the pseudostatic tests of three specimens with different separation ratios under the action of constant axial force have been completed, and the failure patterns and failure modes of the specimens have been obtained. The results show that the variation of the separation ratio has little effect on the failure process and failure mode of the split column, that is, the compressing and bending failure occurs in the split column with different separation ratios. (2) the concrete values of the column failure are obtained by experiments in this paper. The hysteretic curve, skeleton curve, load-carrying capacity, deformation capacity, stiffness change and strain of steel bar are analyzed. The results show that the peak bearing capacity increases and the ductility decreases with the decrease of separation ratio. The energy dissipation capacity is weakened and the stiffness degradation rate is accelerated, which indicates that the partition ratio is an important factor affecting the mechanical performance of the split column. (3) three split-column models with different separation ratios are established by using the finite element Abaqus software, and each split-column model is simulated and calculated. The influence of the variation of the separation ratio on the failure mode, skeleton curve and bearing capacity of the split column is clarified. The accuracy and reasonableness of the model are verified by comparing the test data with the simulation data.
【学位授予单位】：烟台大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TU973

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