【作者】 马千里；

【导师】 叶列平；

【作者基本信息】 清华大学 ， 土木工程， 2009， 博士

【摘要】 本文全面阐述了基于能量抗震设计方法的研究现状,针对钢筋混凝土框架结构基于能量抗震设计方法进行了系统深入的研究。主要研究工作和成果如下:(1)抗震分析用地震动强度指标选取。通过分析SDOF系统和MDOF系统主要地震响应与已有的不同地震动强度指标之间的相关性的方法,对已有的主要地震动强度指标在抗震分析中的适用性进行了分析,并给出了合理建议。(2)静力弹塑性分析方法在RC框架结构中的适用性。以逐步增量弹塑性时程分析结果为基础,分析了传统定侧力推覆分析和多模态推覆分析方法对结构地震响应的准确性,为结构变形和累积滞回耗能的研究奠定基础。(3)结构屈服后刚度对地震响应的影响。研究了结构参数和地面运动参数对剪切型MDOF系统地震响应的影响,讨论总结了提高结构屈服后刚度的方法。在此基础上,针对RC框架结构,提出框架结构应尽量形成整体型屈服机制。(4) RC框架结构“强柱弱梁”机制的研究。介绍了世界主要国家规范“强柱弱梁”设计方法,并针对我国规范设计方法所存在问题进行了研究,同时,对“强柱弱梁”设计方法提出了相应的改进建议。(5) RC框架结构最大层间位移和构件变形预测。提出了具有整体型屈服机制的RC框架结构弹塑性层间位移预测简化方法,既避免了大量弹塑性时程分析,又可以近似考虑地震响应的离散性。(6) RC框架结构累积滞回耗能分布简化计算方法。统计分析了具有不同柱梁抗弯承载力比的RC框架结构累积滞回耗能分布规律,并针对符合损伤模式控制的RC框架结构,提出了累积滞回耗能分布简化计算方法。(7) RC框架基于能量的抗震设计方法。基于本文的研究成果,采用变形和累积滞回耗能双重指标,并结合基于位移抗震设计方法与现有梁、柱构件的含累积耗能指标的损伤模型,建议了RC框架结构基于能量抗震设计方法,并通过算例说明了设计方法的应用。与时程分析方法的对比结果表明,所设计结构各抗震水准下的承载力、变形和累积滞回耗能性能明确,满足性能目标。更多还原

【Abstract】 In this thesis, the state of the art of the energy-based seismic design methodology is expatiated. The analysis and design method based on deformation and energy response of seismic structures is studied and the main achievements of this dissertation are as follows:1. Based on elasto-plastic single-degree-of-freedom (SDOF) and elasto-plastic multi-degree-of-freedom (MDOF) systems, the correlation between different structural seismic responses and variant intensity indices is analyzed using 60 earthquake records. According to the analysis of the correlation, the rational ground motion intensity indices for seismic analysis purpose are suggested.2. Based on the results of the incremental dynamic analysis (IDA), the accuracy of traditional pushover analysis and modal pushover analysis (MPA) to the seismic responses of RC frame structures, especially to the deformation of structures, are analyzed and compared. Finally, the applicability of the commonly-used nonlinear static analysis procedures for RC frame structures is summarized.3. The influence of post-yielding stiffness to the seismic response of structures is studied with 19,600 nonlinear time-history analysis cases mainly based on MDOF systems, and the methods of improving post-yielding stiffness of structures are summarized. It is indicated that, the seismic structures should have enhanced behavior after the structure yielding. For RC frames, the total failure mechanism of structures is preferred.4. The design methods for weak-beam-strong-column RC frames in several national codes are introduced, and the problems in Chinese code are summarized and studied. It is shown that, the excessive amount of reinforcement of beam, the case-in-place floor slabs, the value of column-to-beam strength ratio and several other uncertain factors may influent the weak-beam-strong-column design. Finally, the design suggestions are proposed and the design method is improved.5. A simplified procedure for evaluating the story drifts of RC frames with total failure mechanism is proposed based on several rational assumptions, which is relatively accurate compared with nonlinear static analysis procedures. The proposed estimating procedure can also reflect the dispersion of seismic responses and avoids the large amount of calculation of nonlinear time-history analysis. Consequently, the nonlinear static analysis procedure is used to estimate the deformation demand of structural elements by taking the evaluated story drift as target performance point of each story.6. The distribution of cumulated seismic hysteretic energy of RC frames with different column-to-beam strength ratios are studied based on 3-story, 6-story, 8-story and 10-story frames. The simplified calculating method is proposed according to the results of frames in line with the design requirements for deformation and seismic energy dissipation.7. Based on the two-stage design approaches and the failure criterion determined by deformation and hysteretic energy, the combined energy and displacement-based design methodologies are suggested. A practical example is used to illustrate the design procedure, and it is validated by time history analysis. The results indicate that the suggested energy-based seismic design method for the RC frames can provide adequate deformation and seismic energy dissipating capacities to achieve the designed performance objectives.更多还原