【作者】 张磊；

【导师】 叶列平； 陆新征；

【作者基本信息】 清华大学 ， 土木工程， 2019， 博士

【摘要】 对超高层而言,中小震下,过大楼层加速度会造成非结构构件损坏,带来严重经济损失。同时,多灾害防御和韧性防御已成为国际研究前沿,但现有超高层建筑多灾韧性防御研究相当匮乏。因此,为解决上述问题,即中小地震下楼层加速度控制、大震下结构韧性提升及地震-连续倒塌综合防御,本文提出了一新型结构体系及设计方法,并对体系中关键构件进行了系统研究。主要工作如下:(1)提出了一种新型含减振子结构的地震-连续倒塌综合韧性防御组合框架-支撑筒-伸臂结构体系。介绍了该新型结构体系的主要组成部分,阐述了各组成部分的具体构造及工作原理,给出了各关键构件在不同概率水准地震作用下的性能目标,以及结构在不同类型连续倒塌工况下的内力重分布路径。(2)提出了一种适用于自复位框架节点的新型可更换加劲角钢耗能构件。开展了相应的试验与数值模拟研究,模拟结果与试验结果吻合良好。并提出了加劲角钢耗能构件提供的梁柱连接初始刚度和屈服弯矩的理论计算公式。(3)提出了地震-连续倒塌综合防御组合框架结构(Multi-hazards resistant steel-concrete composite frame,MHRSCCF-1)。开展了常规组合框架和MHRSCCF-1的子结构抗震性能试验和抗连续倒塌性能试验。建立了与试验相应的有限元模型,可较为准确的模拟结构的受力特性。(4)提出可实现韧性防灾的地震-连续倒塌综合韧性防御组合框架(Multihazards resilient steel-concrete composite frame,MHRSCCF-2),提升了MHRSCCF-1的韧性,可实现结构抗震与抗连续倒塌灾变过程的稳定、有序、可控、易修复。开展了MHRSCCF-2子结构抗震和抗连续倒塌性能试验。提出可以考虑不同边界条件的MHRSCCF-2节点转动初始刚度和屈服弯矩理论计算公式。(5)提出利用减振子结构来控制超高层结构中小地震作用下楼层加速度的概念。基于超高层建筑的弯剪耦合模型,探究了减振子结构参数与结构参数对超高层建筑楼层加速度控制效果的影响,提出了最优减振子结构的设计方法。(6)提出了含减振子结构的地震-连续倒塌综合韧性防御组合框架-支撑筒-伸臂结构体系的设计方法。基于整体结构有限元模型的地震弹塑性时程分析及连续倒塌工况分析,验证了新结构体系设计方法的合理性以及有效性。更多还原

【Abstract】 For super-tall buildings,when subjected to service level earthquakes(SLEs)or design basis earthquakes(DBEs),excessive floor acceleration can lead to damage of non-structural components resulting in severe economic losses.At the same time,“multi-hazards resistance” and “resilience” have become important research frontiers in the international disaster prevention community.However,the existing research about structural multi-hazard resilience design method is still rather limited.For super-tall buildings,there are three key challenges,namely,the floor acceleration control subjected to SLEs or DBEs,the structural resilience subjected to maximal considered earthquakes(MCEs),and the multi-hazards resistance.In this work,a new structural system and its corresponding design method are proposed to solve the above three key problems,and the key components of the new structural system are systematically studied.The main research work of this dissertation is summarized as follows:(1)A new type of multi-hazards resilient steel-concrete composite frame-braced tube-outrigger with vibration reduction substructure(VRS)system is proposed.The main components of the new structure system are introduced.The construction and work mechanism of each component are explained.The performance targets of the key components under different probabilistic earthquake levels and the internal force redistribution of structures under different types of progressive collapse conditions are given.(2)A novel replaceable stiffening angle steel(SAS)component is proposed,which can be used in self-centering frames.Corresponding experiments and numerical simulations are carried out,and the simulation results are in good agreement with the experimental results.The theoretical methods of the initial stiffness and the yield moment provided by the SAS components were proposed and validated by the finite-element(FE)models.(3)Multi-hazards resistant steel-concrete composite frame(MHRSCCF-1)is proposed.Seismic and progressice collapse experimental studies on the substructure of the MHRSCCF-1 and the conventional steel-concrete composite frame are conducted.The FE models corresponding to the tests are established,which can accurately represent the mechanical characteristics of the structure.(4)Multi-hazards resilient steel-concrete composite frame(MHRSCCF-2)is proposed,which can make the structural seismic and progressive collapse damage process stable,orderly,controllable and easy to repair.Seismic and progressice collapse experimental studies on the substructure of the MHRSCCF-2 are conducted.The theoretical models used to calculate the initial stiffness and yield moment of the beam-column connection of MHRSCCF-2 are presented.(5)The concept of VRS controlling floor acceleration of super-tall buildings under SLEs or DBEs is proposed.Based on the flexural-shear coupling beam model,the influence of structural and VRS’s parameters on the floor acceleration reduction effect of super-tall buildings is studied through time history analysis under actual ground motions.The design method of optimal VRS is presented.(6)The design method of multi-hazards resilient steel-concrete composite frame-braced tube-outrigger system with VRS is presented.Based on the FE model of the whole structure,seismic nonlinear time history analysis and progressive collapse analysis are conducted to verify the rationality and effectiveness of the design method of the new structural system.更多还原