【作者】 夏雷；

【导师】 姚谦峰； 袁泉；

【作者基本信息】 北京交通大学 ， 结构工程， 2012， 博士

【摘要】 底部框架结构是为了适应现代建筑使用功能要求而出现的一种建筑形式,由于结构存在转换层,导致其受力机理较为复杂,特别是在转换层部位刚度与承载力的匹配关系方面存在较多难题。密肋复合墙结构作为一种新型结构体系,其构造形式可以灵活设计,便于实现结构刚度及承载力的合理调整,在一定程度上适应了底部框架结构的相关要求。因此,课题组将其应用于底部框架结构中,从而提出了底部框架密肋复合墙结构。本文以前期研究工作为基础,充分结合密肋复合墙结构自身的构造特点,采用理论分析与有限元模拟相结合的方法,针对底部框架密肋复合墙结构中存在的几个突出问题进行了较为细致的研究,主要完成的工作及相关成果如下：1.底部框架密肋复合墙梁组合作用效应及影响因素分析基于双参数弹性地基梁理论,将密肋复合墙体等效为复合弹性地基,托梁等效为倒置的弹性地基梁,采用半解析的传递矩阵法求解了竖向荷载作用下墙梁组合界面的竖向应力分布规律,并提出了等效复合地基参数的确定方法。同时,考虑边框柱截面形式、暗梁截面高度、连接柱位置、墙体厚度、密肋框格划分形式以及砌块弹性模量等诸多因素,比较全面地分析了上部墙体的结构构造对墙梁组合作用效应的影响。2.底部框架密肋复合墙结构构件非线性滞回特性分析以试验研究为基础,借鉴现有的非线性分析方法,采用基于材料层次的精细化纤维杆单元模拟钢筋混凝土梁、柱构件,采用等效弹簧单元模拟框格约束条件下的填充砌块,建立了底部框架密肋复合墙结构的“纤维杆件+等效弹簧”分析模型,并提出了考虑强化刚度、软化刚度、退化强度、裂缝闭合、捏拢效应等特性的多参数等效弹簧恢复力模型,进而对低周反复荷载作用下底部框架密肋复合墙结构构件的非线性滞回性能进行了模拟分析,与试验结果符合较好。3.底部框架密肋复合墙结构动力响应时程分析在结构构件非线性分析的基础上,进一步建立了底部框架密肋复合墙结构的空间分析模型,通过弹塑性时程分析研究了结构在水平地震作用下的非线性动力响应规律,重点探讨了转换层上、下的层间刚度比对结构地震反应的影响,模拟了不同刚度比情况下结构的最终破坏形态,并提出了合理刚度比的取值范围。4.底部框架密肋复合墙结构设计计算方法及抗震设计要求基于墙梁组合作用的影响因素分析,参照现有的设计计算方法,考虑砌块弹性模量及墙体厚度的影响,通过多因素正交试验设计及回归分析,建立了托梁内力系数修正值的表达式,进一步完善了底部框架密肋复合墙结构的设计计算方法,并结合相关设计规范及分析结果,提出了相应的抗震设计要求。更多还原

【Abstract】 Structure with frame at the bottom (SFB) is a kind of building style which adapts to the modern building occupancy. As there is a transfer story, the mechanical mechanism of the structure is very complex, and there are many difficult problems, especially in the matching relationship between the stiffness and bearing capacity near the transfer story. As a new kind of structure system, multi-ribbed composite wall structure (MRCWS) has the benefit of a flexible and variable constitution, and it is convenient to adjust the stiffness and bearing capacity of the structure reasonably, which adapts to the related requirements of SFB to a certain extent. Therefore, multi-ribbed composite wall structure with frame at the bottom (MRCWSFB) is proposed with the application of MRCWS in SFB.Based on the former research and with the constitution characteristics fully considered, some crucial issues in MRCWSFB were detailedly studied in this paper by the theoretical analysis and finite element simulation, and the main work done and related results are as follows:1. Analysis on the composite action effect and influence factors of wall beam in MRCWSFBBased on the two-parameter elastic foundation beam theory, the multi-ribbed composite wall is equivalent to a kind of composite elastic foundation, and the trimmer beam is equivalent to a beam inverted on the elastic foundation. And then the vertical stress on the interface of wall beam under vertical loads was solved using a half analytical analysis of transfer matrix method, and the method to determine the equivalent composite foundation parameters was put forward as well. Moreover, with the consideration of cross section shape of ourter columns, height of concealed beams, position of connecting columns, thickness of the wall, division forms of multi-ribbed frame and elastic modulus of blocks, comprehensive analysis was promoted for the influence of upper wall’s constitution on the composite action of wall beam.2. Nonlinear hysteretic behavior analysis for MRCWSFBBased on the former tests and common nonlinear analysis method, the reinforced concrete beam and column components were simulated by the fine fiber element based on material level, and the filling blocks constrained by the multi-ribbed frame were simulated by an equivalent spring element, so that the analysis model of "fiber bar& equivalent spring" was established for MRCWSFB, and the multi-parameter equivalent spring restoring force model was put forward with the consideration of strengthening stiffness, softening stiffness, strength degradation, fracture closure and pinch effect etc., and then the nonlinear hysteretic performance of MRCWSFB was simulated under low reversed cyclic loads, which agreed well with the experimental results.3. Dynamic response time history analysis for MRCWSFBBased on the nonlinear analysis of structural components, the spacial analysis model was built for MRCWSFB. And then the nonlinear dynamic response under horizontal earthquake was analyzed through elasto-plastic time history analysis, and the seismic effect of the stiffness ratio near the transfer floor was mainly discussed. Meanwhile, the final failure modes of the structures with different stiffness ratios were simulated, and the reasonable stiffness ratio range was put forward as well.4. Design method and details for MRCWSFBBased on the influence factors analysis of composite action for wall beam, according to the existing design and calculation method and with the consideration of elastic modulus of filling blocks and thickness of wall, the modification formula for internal force index of trimming beam was put forward by orthogonal multiple-factor experiment and regression analysis, which improved the design and calculation method of MRCWSFB. Furthermore, the corresponding seismic design demands were also proposed due to the tests and analysis results.更多还原