【作者】 邓晖；

【导师】 朱建军；

【作者基本信息】 中南大学 ， 大地测量学与测量工程， 2007， 博士

【摘要】 现代大跨度空间结构的发展虽然起步较晚，但由于其特殊的优越性和挑战性，在世界各国发展十分迅速。进入二十一世纪后，我国大跨度空间结构建设在数量、跨度、型式等方面都有了较大的进展。伴随着我国基础设施建设正进入一个新的发展高潮的同时，也对大跨度空间结构的建设水平提出了更高的要求。大跨度空间结构施工监测与分析是连接设计与施工的桥梁，它不仅是建设中的一个关键环节，而且也是建设中实施难度较大的一个环节。大跨度空间结构施工监测与分析属于大地测量学与防灾减灾工程学交叉的边缘课题，提高施工监测与分析的技术水平将会产生巨大的工程价值与经济效益。本文的研究对象为大跨度空间结构，主要工作是大跨度空间结构变形监测精度指标确定和施工过程监测监控相关理论与核心技术的研究，包括：1．变形监测精度指标确定变形监测精度指标的合理确定是变形监测的核心问题之一。论文系统地探讨了变形监测现行的主要指标和精度要求；首次针对大跨度空间结构范畴，对三个重要定义(允许变形值、临界变形值、安全度)进行了扩充；在总结归纳了确定变形监测精度指标的方法基础上，通过相关实例的研究分析与对比，获得了大跨度空间结构变形监测精度指标确定的方法，并提出了新的观点，进一步完善了变形监测精度指标确定的方法。2．大跨度空间结构监测技术大跨度空间结构监测技术研究是本文研究的核心内容之一。本文首次系统地探讨、整合了在大跨度空间结构施工监测监控过程中外部变形测量、内部应力测量及索力测量相关技术和方法。在外部变形测量方面，本文提出并验证了一套利用常规地面监测技术监测大跨度空间结构几何变形的实用方案及一种简化的差分极坐标测量方法；在应力测量方面，本文提出了一种适用于大型混凝土三角刚架应力监测的新方法，研究了混凝土的收缩徐变对应力测量的影响，并在此基础上建立了一套由振弦式传感器的测试数据推算混凝土结构应力的流程；在索力测量方面，本文探讨了频率法测量索力的原理及实用测量技术。3．有限元法有限元法在大跨度空间结构模拟分析的应用研究是本文的重要理论基础之一。详细地探讨了本文新光大桥和广州会展中心屋盖结构模拟分析中用到的空间杆单元、空间梁单元、板／壳单元和块体单元四种有限单元。然后分别介绍了用这四种单元模拟的结构应具有的几何和受力特征，以及空间杆单元、空间梁单元的位移模式和单元刚度矩阵，薄板理论和20结点六面体单元的形状函数和单元列式。4．广州新光大桥施工控制的结构分析与监测作为理论和技术研究的工程应用实例，论文介绍了新光大桥的施工过程和重要施工工况，系统地研究了新光大桥结构有限元模型的建立和模拟计算，并依据计算结果合理地确定了监测断面和监测点，在采集仪的监测模块平台上研究开发了网络化、远程化数据采集系统，实现了测试数据实时采集与实时处理，通过实测值与理论计算值两者之间的对比分析，从而有利于科学地评判新光大桥各大节段在提升过程中的实时状况和安全度。系统地研究了施工监测监控控制网的建立，拱肋线形指标的有关控制及提高测量精度的措施，从而准确地得到了拱肋线性变化的特性和规律。系统地研究外界温度变化对施工监控的影响，找出了拱肋变化的线性规律和函数式，选择出最佳合龙时机，保证了拱肋的合龙精度和线形要求；测试了大量温度与应力对应关系的实验数据，采用最小二乘拟合推估法，推导出温度修正后的应变计算公式，从而提高了应力测试数据的准确性。在新光大桥的工程实践中，最终实现了新光大桥的高精度合拢，线形、索力和应力均高标准满足了设计要求，经济效益良好。5．广州会展中心屋顶张弦桁架施工监测与分析作为理论和技术研究的工程应用又一个实例，论文系统地提出了适合目前我国最大跨度张弦桁架这种新型结构相关监测的内容与方案，验证了张弦桁架的钢管在冷弯加工后，弦杆刚度有较大的衰退，证明了利用现代大地测量仪器和技术、贴电阻式应变片方式可以满足大跨度张弦桁架监测的精度要求，得到了大跨度张弦桁架在不同施工阶段的几何变形规律和特性。在工程实践中，通过理论分析及与实测值的对比，找出了一种合理的施工张拉方案，保证了施工的顺利进行，同时得到了结构总体刚度有衰减的特性。最终实现了广州会展中心屋顶施工控制指标高标准满足了设计要求，得到了大量对以后类似工程有价值的数据和结论。更多还原

【Abstract】 It is well-known that the modern large span space structure has evolved into the most popular structure type all over the world because of its special advantages and challenge. Turn into 21 century, in our country a great progress has made in the construction of large span space structure on the side of number, span, type, style etc. With infrastructure construction rapidly development in our country, the construction capacity of large span space structure is called for higher level.Function of construction monitoring and analysis is a connection between that of the design and construction. It is not only one of the most important works but also one of the most difficulty works during construction of large span space structure. Large span space structure monitoring and analysis is a crossing subject including geodesy and disaster prevention and mitigation engineering. To raise the level of the technologies of construction monitoring and analysis have great significance for better quality and less expense in large span space structure.The thesis deals with a theory and some research on key technologies of construction monitoring and analysis of large span space structure. The theoretical innovations and main achievement of this dissertation can be summarized as follows:1. Research on confirmation of deformation monitoring precision indexesConfirmation of deformation monitoring precision indexes is one of the keys of deformation monitoring. Firstly, this dissertation systemic introduces main indexes and precision demands presently. Secondly, three important definitions(permissible deformation value, critical deformation value, degree of safety) are extended only for large span space structure. Thirdly, on the basis of methods of confirming deformation monitoring precision indexes summarized, methods of confirming large span space structure deformation monitoring precision indexes are gained by comparison and analysis of correlative examples and new opinions are proposed. Finally, methods of confirming deformation monitoring precision indexes are more perfect.2. Study of large span space structure monitoring technology Large span space structure monitoring technology is one of the keys of the dissertation. Technologies and methods of exterior deformation monitoring, inner stress measurement and cable force measurement are systemic introduced and integrated for the first time in this dissertation for large span space structure construction monitoring. On the side of exterior deformation monitoring, this dissertation proposes and proves the utility monitoring scheme by using general ground monitoring technology and the method of simplification differentiation polar coordinate survey for large span space structure deformation monitoring. On the side of stress measurement, this dissertation proposes an new method of stress measurement suit for mass concrete triangular frame and discusses shrinkage and creep of concrete how to influence stress measurement, and sets up finally a process how to calculate concrete stress through data for piano wire sensors. Finally, on the side of cable forces measurement, this dissertation discusses principle and measurement technology of frequency method.3. Research on finite element methodApplication research on large span space structure FEM simulation analysis is one of important theory basis in this dissertation. Studies four types finite element such as truss element, beam element, shell/plate element and solid element for the Xinguang Bridge and the Guangzhou international conference exhibition center. Then introduces geometric and tension & compression characteristic that should belong to structure for those kinds finite element simulation analysis, displacements distribution and stiffness matrix of truss element and beam element, thin plate bending theory and element shape functions and formulation and integration scheme of 20-node hexahedron.4. Research on Monitoring and structural analysis of the Xinguang Bridge constructionAs a engineering application of the proposed theoretical and technological studies, This dissertation introduces construction procedure and important period of the Xinguang Bridge, systemic studies structural finite element model and simulation calculate, then on the basis of simulation calculate confirms arrangement of the cross-section and point for strain and temperature monitor of the Xinguang Bridge, studies and develops the network and remote monitoring system on the platform of the collection instrument module, realizes gathering and dealing with measured data real time, by comparison actual value with simulation calculate one, then more scientific evaluates true status and degree of safety of the Xinguang Bridge big part of arch during rising up. Systemic studies setting up of construction monitoring control network, control of arch rib linear indexes and improvement of survey precision, then gains linear inflect characteristic and regularity of the arch rib. Systemic studies environment temperature how to influence construction control, finds out linear regularity and function formula of the arch rib, selects optimal closure time, then fully meets requirements of closure precision and linear. By testing a lot of data on temperature and strain and adopting least squares collocation, this dissertation deduces the strain calculate formula that is amended by joining temperature factor, then improves accuracy of stresses testing data. In the Xinguang Bridge engineering practice, as a result, the closure errors of the Xinguang Bridge reach a high accuracy, as well as all the final girder elevation, cable forces and structural inner forces.5. Research on analysis and geometric deformation monitoring of the roof truss-string applied to Guangzhou international conference exhibition centerAs another engineering application of the proposed theoretical and technological studies, this dissertation proposes both the content and the scheme on monitoring of the new type large span truss-string structure which is the largest one in China presently, it is proved chord rigidity happens more attenuation after cold bending of steel tube of truss-string. The measured results are proved that this approach can fully meet high precision requirement demands. Deformation parameters and characteristics of the truss-string in the different construction periods are obtained. In the engineering practice, by comparison calculation value with actual one, a rational construction stretching scheme is found out, then it fully meets construction requirements, at the same time attenuation characteristic of structural system rigidity is found. And as a result, the construction control indexes of the Guangzhou international conference exhibition center roof reach a high accuracy, a lot of valuable actual data and conclusion for similar projects construction and design are obtained.更多还原