基于温度补偿的索张力补张拉修正算法

针对大型复杂预应力空间钢结构施工过程中实测索力与目标索力存在较大差值的问题,在已有研究的基础上,基于温度补偿法并结合找形分析算法,提出了补张拉索力修正的计算策略以及数值计算流程.基于ANSYS软件平台,采用初始应变输入与施加温度荷载输入相结合的方法,编制了补张拉索力修正计算模块,用于施工过程中主动索补张拉的修正计算.该修正计算方法可考虑几何非线性、弹性预应力损失以及群索在张拉过程中的相互影响等因素,能保证补张拉过程符合施工和设计对索力精度的要求,可直接用于指导施工过程补张拉,追踪构件在张拉过程中的力学响应.算例结果表明,该方法是用于实际工程预应力补张拉计算的一个实用而有效的方法.

Algorithm for compensating tension revision of cable force based on temperature compensation

During the construction of large scale complex prestressed spatial structures,considerable difference exists between the real cable force and the design cable force requirement,which cannot be neglected in actual engineering.Based on the current researches,this paper proposes an elaborate calculation strategy and a corresponding numerical calculation procedure for modifying the cable force by means of temperature compensation algorithm combined with generalized form finding analysis algorithm.A computation module of additional revising tension is developed based on the platform of the software ANSYS by using two node cable element.This computation module can be used to control the calculation in the additional revising tension process of active cables.With this module,nonlinearity,elasticity prestressed lose and mutual influence among the cables can be considered,and the accuracy of construction and design requirement can be satisfied in the processing of additional tension construction.Through tracing the mechanical response of members,the module is a guide during the process of additional tension construction.Finally,the analytical results of the examples suggest that this method of additional tension is practically efficient in the process of real prestressed tension construction.