大跨度、大吨位预应力桁架拉索预应力张拉模拟过程分析研究

Simulation of Cable Tension Process on Large-Span and Large-Tonnage Prestressed Steel Truss Structures

为解决大跨预应力钢桁架拉索预紧力施加的精确控制问题,采用有限元数值计算的方法研究拉索张拉的模拟施工过程。该方法结合具体的工程案例并通过精细化的有限元建模,计算预应力拉索张拉过程中不同阶段的拉索内力分布及相互关系,最终建立具有代表性的18榀大跨预应力钢桁架结构两次循环加载的仿真施工过程,并确定了预应力拉索的最大内力值及对应的位置并与工程实际结果相比较,其误差率不超过1%,这与拉索自身结构与所处的区域相关。大跨预应力钢桁架结构拉索张拉过程仿真与工程实际结果比较表明,该施工过程仿真精度高,可以作为工程具体实施的科学指导依据。

This paper presents a finite element simulation of cable tension process of prestressed steel truss, to achieve precise evaluation on pre-tightening forces in large-span truss structures. The simulation is based on a real engineering project,and the internal force distribution at different stages of pre-stressing and cable tension process are calculated utilizing refined finite element model. Finally a reprehensive simulation on 18 large-span prestressed steel truss frames under two cyclic loading is established, and the maximum value of internal force and the corresponding locations are identified. Comparing simulation results to the actual values, the errors are less than 1%, which depend on the structure type and distributive region. Overall, the simulation process and results indicate the construction process can be simulated precisely and the results can be a good reference for real construction projects.