超大跨预应力斜拉网格结构结构设计及施工方法研究

发布时间：2019-01-25 19:24

【摘要】：空间结构作为衡量一个国家土建行业的标杆,近些年有长足的发展,无论在结构形式方面,还是在空间跨度方面,都实现了突破和创新。但是目前空间结构还未曾突破300m跨度的局限,随着人类刚性需求的增加,空间结构仍然有必要朝着超大空间、超大跨度的方向发展。预应力斜拉网格结构作为空间结构的一种独特形式,由网格结构和斜拉结构组成,同斜拉桥同属斜拉体系。而斜拉桥的跨度动辄上千米,因此预应力斜拉网格结构可以借鉴斜拉桥的技术经验朝超大跨度超大空间的方向发展,突破目前300m跨度的局限,以满足人类对大跨度大空间结构的要求。本文的主要任务是针对预应力斜拉网格结构进行超大跨度的结构可行性研究以及施工可行性研究。本文针对预应力斜拉网格结构,进行了总结,包括斜拉网格结构的工程应用、发展现状等。并根据己有的设计理论对斜拉网格结构进行设计分析,其中重点在于使用“未知荷载系数”法确定斜拉索索力值。在进行完结构设计分析后,本文对斜拉网格结构的施工方法进行了介绍,其中分为网格结构的施工和斜拉结构的施工。网格结构的施工方法涵盖了以高空散装法、分块滑移法、整体安装法等为代表的传统网格结构施工方法以及以Pantodome体系法、液压整体提升法、液压整体顶升法为主的新型网格结构施工方法；斜拉结构的施工包括桁架柱的施工、斜拉索的安装与张拉,本文也做了简述。基于有限元软件Midas,本文对500m跨度的预应力斜拉网格结构进行建模分析。根据《建筑结构荷载规范》以及《钢结构设计规范》的相关要求,对结构进行设计分析。考虑结构恒载、活载、风载、温度荷载、拉索初拉力荷载以及反应谱作用,对斜拉结构以及网格结构进行变形验算、承载力验算、反力计算以及振型分析,其中结构最大截面P1000×100,总用钢量约7.3万吨,平米用钢量420kg/m2,在同级别跨度范围内属于较为经济的结构体系；结构最大挠度920mm,满足了相关规范的的要求。验证了结构的经济性、合理性、可行性；并对采用分步顶升法与液压整体顶升法的网格结构施工方案、吊装法搭配缆风绳的桁架柱施工方案以及采用一端牵引安装法或者天伦循环法安装法并基于退化补偿法的分批次同时张拉多根拉索的拉索施工方案进行施工模拟分析。在施工过程中,结构所产生的最大位移为345mm,各个杆件的最大应力也均低于钢材的屈服强度；此外,在拉索张拉方面,选用了合理的找力分析方法以及张拉控制方法,使张拉迭代两次便可得到设计索力值, 验证了施工方案的安全性、合理性、可行性。
[Abstract]:As a benchmark to measure a country's civil engineering industry, spatial structure has made great progress in recent years. In terms of structure form and space span, it has achieved breakthrough and innovation. However, at present, the space structure has not broken through the limitation of 300m span. With the increase of human rigid demand, it is necessary for the space structure to develop towards the direction of super-space and super-span. As a special form of spatial structure, prestressed cable-stayed grid structure is composed of grid structure and cable-stayed structure, and the same cable-stayed bridge belongs to cable-stayed system. However, the span of cable-stayed bridge is often thousands of meters, so the prestressed cable-stayed grid structure can use the technical experience of cable-stayed bridge for reference in the direction of super-large space, and break through the limitation of 300m span at present. In order to meet the human requirements for large span and large space structure. The main task of this paper is to study the structural feasibility and construction feasibility of the prestressed cable-stayed grid structure. This paper summarizes the prestressed cable-stayed grid structure, including the engineering application and development status of the cable-stayed grid structure. According to the existing design theory, the design analysis of cable-stayed grid structure is carried out. The key point is to use the method of "unknown load coefficient" to determine the force value of cable-stayed cable. After structural design and analysis, this paper introduces the construction method of cable-stayed grid structure, which includes the construction of grid structure and the construction of cable-stayed structure. The construction methods of grid structure include the traditional grid structure construction method, such as high-altitude bulk loading method, block slip method, integral installation method, and Pantodome system method, hydraulic integral lifting method, etc. A new construction method of grid structure based on hydraulic integral lifting method; The construction of the cable-stayed structure includes the construction of the truss column, the installation and tensioning of the stay cables. Based on the finite element software Midas, this paper models and analyzes the prestressed cable-stayed grid structure with 500 m span. According to the requirements of the Code of load for Building structures and the Code for Design of Steel structures, the design of structures is analyzed. Considering the effects of dead load, live load, wind load, temperature load, cable initial tension load and response spectrum, the deformation check, bearing capacity calculation, reaction force calculation and mode analysis of cable-stayed structure and grid structure are carried out. The maximum cross section P1000 脳 100, the total steel consumption is about 73000 tons, and the square rice steel is 420 kg / m ~ 2, which belongs to the more economical structure system in the same span range. The maximum deflection of the structure is 920mm, which meets the requirements of the relevant specifications. The economy, rationality and feasibility of the structure are verified. And the construction scheme of grid structure with stepwise lifting method and hydraulic integral lifting method is discussed. The construction scheme of truss column with cable wind rope by hoisting method and the cable construction scheme by using one-end traction installation method or Tianlun cycle method and based on the degradation compensation method are analyzed. In the construction process, the maximum displacement of the structure is 345mm, and the maximum stress of each member is lower than the yield strength of steel. In addition, in the aspect of cable tension, reasonable force finding analysis method and tension control method are selected, so that the design cable force value can be obtained twice by tension iteration, which verifies the safety, rationality and feasibility of the construction scheme.
【学位授予单位】：太原理工大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TU399;TU745

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