【作者】 肖明葵；

【导师】 白绍良； 赖明；

【作者基本信息】 重庆大学 ， 结构工程， 2004， 博士

【摘要】 以基于性能的抗震设计思路为基础,针对影响结构抗震性能的位移和滞回耗能反应这两个主要因素,全面阐述了目前世界范围广泛开展的基于性能的抗震设计的研究现状,深入剖析了存在的问题,并展望了发展趋势,对评估结构抗震性能的位移和能量反应的分析方法展开研究。取得了如下主要研究成果:1.针对目前主要用于结构抗震性能评估的能力谱方法中采用等效高阻尼弹性需求谱在理论和应用上存在的问题,全面分析了影响反应谱的结构动力参数和地震动参数,基于大量强震记录,采用时程分析方法,计算出具有统计意义的弹塑性加速度反应谱、弹塑性位移谱、弹塑性位移与弹性位移的比值反应谱及其谱曲线的简化计算公式。给出了弹塑性需求谱曲线,提出并建立了基于弹塑性需求谱的能力谱方法和屈服位移改进的计算方法,为基于性能的抗震设计方法提供了一条新途径。算例表明该方法具有一定的工程适用性。2.针对目前抗震设计中仅考虑结构位移反应进行结构抗震性能评估不能正确评价结构抗震性能的问题,提出补充耗能量反应评估结构抗震性能的建议,分析影响地震能量反应的地震动及结构动力参数,分别讨论各种参数对能量反应的不同影响,得出具统计意义的弹性和弹塑性总输入能量谱及滞回耗能谱;以及滞回耗能在总输入能中所占比例的比值谱。拟合出计算谱曲线的简化计算公式,拟合精度高,便于工程设计应用;考虑持时影响对地面运动分类,输入按持时定义分类的地面运动,计算出单自由度体系的位移时程反应和滞回耗能增量反应,得出不同类型地面运动的最大塑性位移和滞回耗能增量的反应规律,推导出由滞回耗能增量求最大弹塑性位移的计算公式和由此估算结构延性的方法,解决了长期以来依赖单调加载只能近似估计抗震结构整体延性的问题,同时建立了抗震结构的位移和滞回耗能这两个不同反应之间的关系,可为综合研究结构抗震性能提供研究基础;研究杆系模型分别在 7 度和 8 度长持时、中等持时多频谱型和近场短持时脉冲型地面运动作用下的能量反应,得出在不同类型的地面运动作用下,滞回耗能量可能相差几倍甚至上十倍的规律的基础上,并通过对于框架结构不同时刻能量反应和出铰规律的分析,得出框架结构能量薄弱层的概念。提出结构抗震设计应同时考虑位移和耗能量薄弱层的建议和用能量谱估计结构滞回耗能量方法,指出对于不同地震动的输入,应同时控制结构的位移和累积滞回耗能反应;在评判结构破坏时,应加入耗能指标;在考虑滞回耗能的双重损伤指标中应计入一定比例的梁的滞回耗能量的建议,为双指标损伤准则的工程应用提供研究基础。 I<WP=6>中文摘要3.讨论了采用时程分析方法进行能量反应分析所需要的地震地面运动输入的选择问题,指出采用时程分析方法计算结构的能量反应时,所选地震波应考虑地震波的持时的影响,提出直接基于体系的总输入能量反应对地震波进行按持时影响分类的方法。该方法仅通过计算结构的弹性总输入能量即可得出地震动的分类,方法简单,概念明确,可方便地应用于工程抗震设计中。4.分析了时程分析法的求解方法的精度和稳定性,以及恢复力模型中采用精确公式求拐点的方法,并推导出求拐点的精确计算公式;5.提出以实际框架结构单位质量的滞回耗能量与等效单自由度体系的单位质量耗能量相等的原则,识别等效弹塑性单自由度系统的屈服位移的方法。通过逐次迭代运算,得出了等效体系的屈服位移d*y。识别的多波统计结果与 FEMA356的d*y接近,方法概念明确,计算简单,结果可信。更多还原

【Abstract】 On the basis of performance based design, which is discussed widely in theworld, the work of the paper aims at the displacement and hysteretic energy responsesof seismic structures. The state of arts is reviewed and the disadvantages of theperformance based design are expatiated and the research trends are presented. Theanalysis methods of displacement and hysteretic energy responses of seismicstructures are discussed and mainfindings are listed as follows: 1. The structural dynamic parameters and earthquake parameters which haveeffect on response spectrum are analyzed fully based on the investigation of thedisadvantages of the method of equivalent high damp ratio elastic demand spectrummainly used for evaluation performance of seismic structures. The elastoplasticacceleration spectrum, elastoplastic displacement spectrum and the ratio spectrum ofthe elastoplastic displacement to the elastic displacement are calculated in statisticalsense by using a great deal of earthquake digital records with time history analysismethod. The simplified formulas of these spectra are set forth. The improve capacityspectrum method based on the elastoplastic demand spectrum and method forcalculating yield displacement are founded. Anew approach of the performance baseddesign is provided with the improved capacity spectrum method. The applicability ofimproved capacity spectrum method in seismic engineering is proved by theexamples. 2. The suggestion of appending the capacity of hysteretic energy responses in theevaluation of the performance of seismic structures is proposed to solve the problemwhich the performance and capacity of seismic structures cannot be accuratelyevaluated by only considering the displacement response. The total input energyspectrum and hysteretic energy responses spectrum and the ratio spectrum of thehysteretic energy to the total input energy are calculated in statistical sense based onthe analysis of the influence of the earthquake parameters and structural dynamicparameters on the spectrum. The simplified formulas of these spectra which areprecise and can be conveniently used forengineering purpose are regressed. The earthquake ground motions are classified by considering the duration ofthem and the displacement time-history and hysteretic energy increment response ofSDOF are calculated. The relationship between the maximal plastic displacement and III<WP=8>英文摘要hysteretic energy increment for different types of earthquake ground motions arefound which can solve the problem that the structural global ductility can only becomputed approximately rely on the method of monotony loads and that can also bethe basis of the integrated evaluation of the capability of seismic structures. The energy response of bar system of frame structures which are subjected tolong duration type waves, middling duration with multi-frequency components typewaves and short duration impulse waves with the intensity of 7 and 8 degree areanalyzed respectively. The results show that the energy response discrepancy is a fewtimes, and in some cases may be ten times. For the stories of weak resistance capacity,both the displacement and hysteretic energy should be checked in seismic designbased on structural performance. The hysteretic energy amount should be consideredwhen judging whether the structure is damaged. The suggestion, which hystereticenergy dissipated by beams and girders should be taken into account when the failurecriterion is determined by displacement and hysteretic energy amount, are presented. 3. The method of selecting input earthquake waves in which the duration isrequired to be considered in the analysis of hysteretic energy using time-historyanalysis is discussed. The method of selecting input earthquake waves based onhysteretic energy response by using total input energy spectrum is suggested. Theadvantage of the method proposed is simple, definition and convenience更多还原