跨度120m三角锥体钢结构施工滑移监测方法研究

大跨度钢结构的滑移是一个动态过程，滑移推力、环境荷载、轨道承载力、轨道平顺性等因素对结构准确就位均有影响。为此，提出了一种能够监测滑移施工过程结构安全、稳定及滑移同步性的方法，该方法通过模拟分析施工滑移过程，准确预判滑移中结构出现损伤的位置和程度，提前采取措施；通过实时在线监测结构滑移施工过程中多项参数的变化，避免滑移过程中结构的应力集中、局部变形过大、脱轨、失稳及倾覆。以大同美术馆钢结构屋盖滑移施工监测为例，在滑移前对滑移施工过程进行模拟分析和监测系统安装，对滑移阶段结构关键构件的应变、位移、构件变形及环境温度进行实时监测、分析与反馈。结果表明：大跨度钢结构滑移受温度、轨道平顺性、轨道处结构变形值、顶推设备误差影响；采用有限元模拟分析、现场监测、实时分析与反馈的监测方法,可有效控制滑移过程中结构的内力、变形、各轨道滑移的同步性及结构的整体稳定性。

Research on construction slip monitoring method of spatial steel structure with triangular cone shape spanning 120 meters

The sliding of long-span steel structure is a dynamic process, and factors such as sliding thrust, environmental load, track bearing capacity, and track smoothness all affect the accurate positioning of the structure. Therefore, a method that can monitor the structural safety, stability, and synchronization of the sliding construction process was proposed. This method can accurately predict the location and degree of structural damage during sliding and take measures in advance by simulating and analyzing the construction sliding process. To avoid stress concentration, excessive local deformation, derailment, instability, and overturning, the changes of parameters in the construction process of structural sliding were monitored in real-time. Taking the steel structure roof of Datong Art Museum as an example, before the slip, the sliding construction process was analyzed and a monitoring system was installed. The system was used for real-time monitoring, analysis, and feedback on the strain, displacement, and deformation of the key components of the structure as well as ambient temperature during the sliding process. The results show that the sliding of long-span steel structure is affected by temperature, track smoothness, structural deformation value at the track and jacking equipment error. The monitoring methods that combine finite element simulation, on-site monitoring, real-time analysis and feedback, can effectively control the internal forces, deformation, synchronization of the sliding of each rail and the overall stability of the structure during the slip process.