【作者】 王春林；

【导师】 吕志涛；

【作者基本信息】 东南大学 ， 结构工程， 2005， 硕士

【摘要】 悬挂建筑结构是高层建筑中一种合理的新型体系,能够充分利用高强材料的力学性能,带来建筑室内和底部大空间,解决建筑功能与结构构造之间的矛盾,有利于抗风和抗震,实现建筑物的坚固、实用和艺术美的三方面的统一,将产生良好的社会和经济效益。核筒悬挂减震结构体系将结构方案和减震措施巧妙结合起来,减震效果显著,为高层和超高层建筑的结构控制和减震理论的发展开拓了新的思路。为此,本论文专门研讨了核筒悬挂建筑结构的减震及CFRP的应用中的若干问题。在本论文中:首先,对单段核筒悬挂结构,给出了设计要点,推导了在地面简谐动力作用和白噪声作为地震加速度激励输入下结构的位移和加速度的频率传递函数。详细分析了阻尼比、频率比和悬挂质量比等参数对结构幅值响应的影响。在已有的分析结果上,给出了主体结构无阻尼情况下的结构响应最优的影响参数解析表达式和主体有阻尼情况下的数值优化分析结果,并给出了优化的目标函数和约束条件,总结出了参数优化设计的基本思路。其次,采用频域分析和时域分析的方法,深入分析了多段核筒悬挂减震结构体系在地震激励作用下的响应规律。分析表明:核筒悬挂减震结构有着良好的减震效果,且其减震效果与主次结构频率比f及次结构阻尼比ξs有关;随着频率比的增大,核筒顶点的侧移先减小后增大,核筒与悬挂楼段的相对位移减小;存在最优频率比,可使得核筒顶点位移最小;随着阻尼比的增大,核筒顶点的侧移略有减小,核筒与悬挂楼段的相对位移减小。再次,建立了核筒悬挂减震结构的有限元分析模型。模态分析表明,核筒悬挂减震结构的模态主要以核筒和悬挂楼段的各自振动为主。时程分析表明,核筒悬挂建筑结构有着良好的减震性能:核筒的顶点侧移可以减小到55%左右;核筒的基底剪力可以减小到65%左右。提出了核筒悬挂减震结构的参数设置方法及步骤,能够较快地得到核筒悬挂减震结构的关键参数设置。最后,对核筒悬挂建筑结构中的悬挂大梁进行了分析,阐述了配置CFRP索作为预应力索的悬挂转换大梁的分析与设计方法,并以具体配置实例说明转换大梁的设计步骤。更多还原

【Abstract】 Suspended building structure that conforms to nature laws is a new kind of system in highrise buildings. The high-strength building materials are of full use in this system. Because it can bring us a big room in the building, it is possible to relax the contradiction between usable function and structural construction. Suspended system can be propitious to resist wind loads and seismic effects and realize the unity of safety, suitability and beauty, so it is of good benefit to the society and economy. Core-tube suspension building structure control system, combining the structural control devices with the structural layout, can reduce the reaction under earthquake loads effectively, which is a new control method for the development of highrise buildings. Because of this, this paper discusses several problems about core-tube suspended building earthquake-reducibility and the application of CFRP.Firstly, design points for an analytical model for single-section hanger on core-tube are briefly listed. The frequency transfer functions of relative displacement and absolute acceleration are derived under action of harmonic and white noise ground excitation. Some parameters, such as the damping, frequency and suspended mass ratio, have an important effect on structure design. Based on the recent achievements, analytic expressions about influencing factors are given when the structure is optimized and the primary structure without the damp. numerical values are presented when the primary structure with the damp. The objective, constraints and basic measure are summarized about the design of structural parameters. Secondly,Frequency-domain and time-domain analysis methods are applied. The rules of reactions of suspended structures under the earthquake excitation have the similar features. By proper design and optimization, suspended structures can reduce the reactions remarkably. The effect is relative to the frequency and damping ratio. With the increment of the frequency ratio, the top displacement of the core firstly declines and then increases, and the relative displacement between the core and the suspended floors descend;The optimum frequency ratio must exist and leads to that the top displacement is minimum; with the increment of the damping ratio, the top displacement change a little, and a relative displacement descends.Thirdly, finite element analysis model about core-tube suspended structure is constructed. Modal analysis shows that suspended structure’s modes are mainly made up of each vibration between core and suspended floors. The time history analysis shows that the top displacement of the core decreases to 55% and the base shear force of the core decreases to 65% in comparison with the uncontrolled suspended structure. The measures and steps of parameter setting are summarized, with which we can rapidly solve key parameters of the suspended structure.Finally, the suspending girder of the core-tube suspended structure is analyzed, and the methods of analysis and design are given for the suspending girder which is prestressed by CFRP cable. The design steps are illuminated by an example for the girder in elastic stage.更多还原