【作者】 王斌；

【导师】 郑山锁；

【作者基本信息】 西安建筑科技大学 ， 结构工程， 2010， 博士

【摘要】 型钢高强高性能混凝土(SRHSHPC)结构以其优良的抗震性能和耐久性而被广泛应用于设防烈度较高地区的高层、超高层建筑以及高耸、大跨和重载结构中。本文采用物理模型试验、理论分析及数值模拟相结合的研究手段,对SRHSHPC构件及其框架结构,尤其是框架柱的地震损伤进行了系统的研究。首先研究了地震作用下SRHSHPC框架柱的损伤演化过程。通过改变轴压比、体积配箍率、含钢率、加载制度对12榀SRHSHPC框架柱试件进行了低周反复加载试验,得到了试件在经历不同次数循环加载后其极限承载、变形和耗能能力的变化规律,并从损伤的角度系统地分析了不同设计参数及加载制度对试件荷载-位移滞回曲线、骨架曲线、刚度和强度退化、变形能力、滞回耗能等的影响。研究结果表明,试件的损伤过程可以分为无损、损伤稳定增长、损伤急剧增长三个阶段；随着循环次数和位移幅值的增加,试件损伤逐渐累积,使其刚度、强度不断退化,耗能能力以及极限变形能力不断降低；与变幅循环加载相比,常幅循环加载下试件的损伤演化过程较为缓慢,滞回耗能总量相对较大。研究结果为进一步建立能够描述SRHSHPC框架柱损伤程度的地震损伤模型,揭示损伤对框架柱力学性能的影响提供了试验支撑。基于低周反复荷载作用下SRHSHPC框架柱的损伤试验研究结果,总结和分析了已有地震损伤模型存在的不足。对框架柱的地震损伤特征与效应进行了分析,建立了能够较全面反映水平地震作用下构件力学特性变化的基于变形和能量组合的非线性双参数损伤模型。模型合理地考虑了荷载循环次数对构件极限抵御能力(极限耗能和变形能力)的影响以及加载路径对损伤量值的影响。对损伤模型中相应的参数进行了分析,给出了其具体定义和表达式。结合试验结果,对损伤模型的有效性进行了验证。结果表明,该模型能够较好地描述SRHSHPC框架柱的地震损伤演化过程与程度,且理论上更为合理。研究结果为该类结构构件的地震损伤评估以及基于损伤的抗震设计方法的建立提供了理论依据。根据SRHSHPC框架柱低周反复加载试验获得的滞回曲线,建立了考虑损伤影响的滞回模型。基于作者所提出的地震损伤模型给出了循环退化指数的确定方法,以此对框架柱各阶段的性能退化进行理论描述,进而建立了基于损伤的SRHSHPC框架柱的恢复力模型。通过试件滞回曲线的试验值与计算值的对比分析,验证了模型的适用性与准确性。结果表明,本文所提出的恢复力模型可准确描述SRHSHPC框架柱在反复荷载作用下的滞回特性。为研究构件损伤向结构损伤迁移转化的多尺度效应,基于课题组前期进行的SRHSHPC框架结构拟静力试验研究结果,揭示了梁、柱构件破坏与局部结构破坏以及整体结构破坏三者之间的关系。根据SRHSHPC框架结构的损伤演化过程,通过合理假定,建立了能够反映构件损伤、局部结构损伤以及整体结构损伤三者之间迁移演化规律的地震损伤模型。结合框架结构的损伤指数,以及试验破坏过程观察,给出了SRHSHPC框架结构的损伤状态及相应的损伤指数范围。更多还原

【Abstract】 Steel reinforced high strength and high performance concrete (SRHSHPC) structures possess excellent seismic behaviour and good endurance, so they were applied to high-rise, super high-rise buildings as well as towering, long-span and heavy-load structures in the high intensity earthquake zone widely. This paper was devoted to studying on seismic damage of SRHSHPC members and frame structures, especially seismic damage of frame columns by the way of combining physical model experiment, theoretical analysis and numerical simulation.Firstly, the damage evolution of SRHSHPC frame columns was investigated through low cycle reversed loading experiment of 12 frame column specimens with various axial compression rations, stirrups ratios, steel rations and loading histories. The change law of the ultimate bearing capacity, ultimate deformation and ultimate hysteretic energy dissipation of specimens subjected to different numbers cycle loading were obtained. The influence of design parameters and loading history change on loading-displacement curve, skeleton curve, strength and stiffness degradation, deformability and energy dissipation capacity were analyzed from the damage viewpoint. The results show that the damage process of specimens can be divided into three stages:undamaged, damage developed stably and damage developed rapidly. With the increase of cycle number and displacement amplitude, the damage of specimens is accumulated gradually, which causes strength and stiffness degradation and decrease of energy dissipation capacity and ultimate deformability. Compared with variation displacement amplitude cycle loading, the process of damage evolution of specimens is slower under constant displacement amplitude cycle loading, and the amount of the energy dissipation of specimens is comparably larger. The research can supply experimental data for establishing seismic damage model and revealing the effect of damage on mechanical property of SRHSHPC frame columns further.The deficiency of existing seismic damage models was concluded and analyzed. In the light of the test results, the seismic damage characteristic of SRHSHPC frame columns was analyzed. Based on the nonlinear double parameters combination of deformation and energy, the damage model, which can well reflect the mechanical characters change of members subjected to horizontal earthquake action, was established by reasonably considering the effect of cycle number on ultimate resistance capacity (ultimate deformation and ultimate energy dissipation capacity) of members, and the effect of loading history on damage etc.. According to the test results, the related parameters were defined and fixed in the damage model proposed inhere. Finally, the validity of damage model was verified by comparison with the test results. The result shows that the damage model proposed can well describe the seismic damage evolution process and degree of SRHSHPC frame columns, and is more reasonable in theory. The study results will supply the theory support for the seismic damage assessment and the establishment of damage-based earthquake-resistant design method of SRHSHPC members.According to the experimental hysteretic curves, the hysteretic model for SRHSHPC frame columns was proposed by considering the effect of damage. Based on seismic damage model obtained inhere, the cycle deterioration index was introduced to describe the performance degradation of SRHSHPC frame columns at different stages theoretically. Then, the damage-based restoring force model of SRHSHPC frame columns was established. By comparing the test results with calculation results for hysteretic curve, the applicability and accuracy of the proposed model was verified. The results show the given restoring force model can well describe the hysteretic behaviour of SRHSHPC frame columns under low cycle reversed loading.The test of SRHSHPC frame structure carried out by companion previously was intorduced to study the multi-scale effect of migration and transformation from member damage to structure damage. The relationship of member, local structure and global structure failure was studied. Based on the damage evolution process of SRHSHPC frame structure, the global damage model, which could reflect migration and evolution law from member damage to local damage and global damage, was established through the reasonable assumption. Finally, the damage states and corresponding damage index range of SRHSHPC frame structure were defined by combining the damage indexes and the test failure process of frame structure.更多还原