施工技术2010年8月 忆CONSTRUCTION TECHNOLOCY第39卷第8期
千斤顶单元法在大跨度钢屋盖拆撑 过程数值模拟中的应用
刘学武，郭彦林，郭宇飞 （清华大学土木水利学院，北京100084） [摘要】大跨度钢屋盖拆撑过程分析是目前大型工程建设中常遇到的施工力学问题，其求解的难点在于千斤顶工 作机理、临时支撑与主体结构脱离和接触以及临时支撑回弹现象的模拟，尚未得到有效解决。
基于通用有限元软 件平台，利用其模块中的只压不拉杆单元和经典梁单元的独特性质，把这两个特性不同的单元并联在一起，通过耦 合单元两端相应节点的自由度和修正单元的刚度，构造一种组合型千斤顶单元。
引人刚化系数α和软化系数β.分 别对杆单元和梁单元的轴向刚度进行修正，研究给出了α和B的取值范围，使组合千斤顶单元具有实际千斤顶的 性质。
建立了拆撑过程分析的千斤顶单元法，能够模拟拆撑过程中千斤顶和临时支撑的工作机理及其与主体结构 之间的相互作用。
算例分析表明，千斤顶单元法理论正确，应用方便，可以用于实际工程中拆撑过程的模拟，能够 分析主体结构及临时支撑内力和变形的变化历程。
[关键词]大跨度钢屋盖；拆撑过程；施工力学；千斤顶单元法 [中图分类号】TU311.4[文献标识码]A[文章编号】1002-8498（2010）08-0024-05 Application ofJackElementModelforNumericalSimulation ofRemovingTemporarySupportsof Large-spanSteelRoof Liu Xuewu, Guo Yanlin,Guo Yufei (School of Civil Engineering,Tsinghua Universty, Beijing 100084， China) AbstractSimulation of removing temporary supports of large-span steelroof isconstruction mechanical problem frequently met in the construction of large structures recently.There are few approaches available to solve the problem effctively. Based on the finite element program, a jack element model used to simulate removing temporary supports of roof is presented and discused. The jack element model is posed of a presson-only link element and a classical beam element, and the two elements are modified by two coefficient α and β. The jack element model behaves as a real jack and it can simulate accurately the separation and contact between the main structure and the jack fixed on the temporary suppor, as wellasrebound of temporary supports during the processofremoving temporary supports.The results obtained demonstrate that the jack element model can be used to pute effectively and accurately the internal force and deformation of the steel structural roof and temporary supports during the construction process. Key words:large-span steel roof; removing temporary support; construction mechanics; jack element model 随着北京奥运会的召开，我国涌现出诸多大体量、时可以减小安装过程中主体结构的内力和变形，提高 造型复杂的大跨度钢结构建筑。
这些建筑的建设不仅施工的安全度，在实际工程...
