【作者】 熊伟；

【导师】 吴敏哲；

【作者基本信息】 西安建筑科技大学 ， 结构工程， 2005， 博士

【摘要】 大跨度张力结构,由于受力合理、刚度大、重量轻、制作安装方便,目前在我国得到了广泛的应用,例如张弦桁架(梁)结构。本文以广州国际会议展览中心的设计资料和预应力张拉施工时的检测数据为背景,分析了目前国内外张弦桁架(梁)的研究资料,总结了张弦桁架中预应力的作用;同时针对张弦桁架的特点,提出了适于张弦桁架的设计方法。将张弦桁架的形状设计(零放样状态)与结构刚度设计分成两步,既简化了张弦桁架形状设计参数,又能较好满足结构荷载态时的形态要求。对目前急需解决的张弦桁架的形态优化及竖向抗震设计方法进行了深入研究。 提出了张弦桁架的形态优化设计方法。首先采用结构离散法,将实际结构分为桁架、拉索、撑杆三部分子结构,每一子结构采用独立的优化模型;为了保证各子结构之间的协调,采用传递矩阵法来传递变形协调参数;由于优化时采用的是形状优化为主,故优化结果的实用性很重要,为了保证优化结果能按预期目标发展及满足实际需要,在优化时引入CAD辅助设计,强化了设计目标的可控性及可预见性;同时建立了张弦桁架的形态优化数学模型,并引入先进的优化算法,如遗传算法等。 建立了桁架子结构优化数学模型,推导了适于张弦桁架的桁架合理拱轴线形,通过对撑杆的研究,提出了多种撑杆设计方法,对桁架及撑杆的影响因素进行了深入分析。建立了张弦桁架拉索内力优化设计方法,推导了拉索工作内力简化计算公式,并对拉索内力影响因素进行了分析。对某实际张弦桁架结构采用形态优化设计方法进行优化设计,与原张弦桁架对比分析,验证了本文提出的优化方法的有效性。采用非线性分析方法研究了预应力与几何大变形的影响,并进行了结构极限承载能力和稳定性研究。 对大跨度张弦桁架的自振频率、振型及影响因素进行了分析。对60米、80米、100米、125米、150米跨度模型采用振形分解反应谱法和时程分析方法进行分析,得到了张弦桁架在小震、大震作用下结构最大动内力系数与动内力分布规律,不同地震波作用下结构响应差别,反应谱法结果与时程法结果差别,跨度对地震响应的影响,挠度变化规律,对拉索是否会松弛的影响等。给出了地震作用下的张更多还原

【Abstract】 Large-span tension structure are extensively used in china now, because of stress fit distribution, large stiffness, light weight, easily making and installing, such as truss(beam) string structure. On the base of data of designing and pre-stress stretching execution of Guangzhou International Convention & Exhibition Center, analyzed all acquired data about truss(beam) string structure , generalized effect of pre-stress on it , at the same time, a method of truss string structure designing is presented in this paper. Truss string structure designing include two steps, shape design(initial shape) and stiffness design, it decreased designing variables and well satisfied shape-state requirement. It is main investigating shape-state optimization and vertical seismic design method of large-span truss string structure in this paper.It is brought forward that shape-state optimization method of truss string structure. First adopt structure discrete method, truss string structure should be divided into truss, string, strut substructure, every substructure has its optimization model. In order to assure coordination, transmitting deform parameter adopted transfer matrix method. This optimization method main is shape optimization, so it is very important that applicability of acquired results, in order to assure results are expectant and meet effective demand, add CAD assistance design, ensured controllability and predictability of calculation results. Meanwhile, shape-state optimization model of truss string structure is founded, and advanced optimization algorithm is adopted, such as genetic algorithm.Optimization model of truss substructure is created, arch axial line shape optimization design of it is studied in this paper, many strut design method are presented through researching of strut, deepgoing analyzed affect factors of truss and strut. Optimization design method of string force, simplify computing method of string force is derived, and analyzedits affect factors. It is adopted that shape-state optimization method of truss string structure on practical structure, results compared with practical truss string structure, effectiveness is verified of established optimization method in this paper. It is studied that affect of pre-stress and geometric large deformation adopting nonlinear analysis method, ultimate bearing capacity and stability are also studied.It is studied that natural frequency, vibration mode and influencing factor of large-span truss string structure. Analyzed by time history method and response spectrum method on 60m, 80m, 100m, 125m, 150m span model, it is got that maximal seismic internal force factor and distribution of truss string structure under small earthquake and large earthquake, structure response difference under different seismic wave, results’ difference of time history method and response spectrum method, influence of span on seismic response, change law of deflection, influence of cable slackness etc. It is given that seismic internal force calculation sketch and relative parameter of truss string structure under earthquake.It is got that equivalence vertical seismic load and distribution law of seismic internal force, through statistical analysis of calculated results adopted much seismic wave input, and compared with results got by response spectrum method. Against with seismic design standard, adoption two stage design method, it is studied that value and distribution of seismic load and seismic internal force, and equivalence vertical seismic load of different yard condition is also studied. It is the results that equivalence vertical seismic load distribution is triangle(medium span large, couple of end small), number value related on yard condition.New method of fit design and calculate equivalence vertical seismic load of truss string structure is presented through studying shape-state optimization and seismic response. Investigation main problem of large-span truss string structure, the conclusion also could be referred by other large-span structure.更多还原