多阶段预应力空间网架结构一次张拉计算法

该文提出多阶段预应力空间网架结构一次张拉计算法,将某一阶段第i次对i预应力杆增加的预应力值作为未知数,通过结构力学方法建立该阶段预应力准则方程式并求解之。然后可计算该阶段i次预应力各预应力杆的控制值(包括各预应力杆原有的内力值),后张预应力对先张预应力的影响值,以及网架结构杆件内力和节点变位,直至该阶段最后一次预应力时得到该阶段各预应力杆的设计内力值及网架结构内力和变位。重复这样的分析计算可得到多阶段预应力网架结构预应力杆的最终内力控制值及网架杆件内力和节点变位。采用该方法,预应力杆的内力值在预应力张拉过程中无需调整,可一次性完成预应力施加操作过程。该文中附有算例说明,计算结果表明:提出的多阶段预应力空间网架结构一次张拉计算法是正确、可靠和有效的。

A single tension calculation method for multi-stage prestressed space grid structure

In this paper, a one-stretch calculation method for multi-stage prestressed space grid structure is presented. The prestress value of the i prestressed bar in a certain stage is taken as the unknown, and the prestress criterion equation is established and solved by structural mechanics method. Then we can calculate the control value of each prestressed rod i times in this stage (including the original internal force value of each prestressed rod), the influence value of post-tensioned prestressed stress on the pre-tensioned prestressed stress, and the internal force and node displacement of the struts of the grid structure until the last time of prestressing in this stage. The final internal force control value, internal force and joint displacement of the prestressed bar of the multi-stage prestressed grid structure can be obtained by repeating this analysis and calculation. With this method, the internal force value of the prestressed rod does not need to be adjusted in the process of prestressed tension, and the operation process of prestressed application can be completed at one time. An example is given to illustrate that the calculation results show that the proposed method is correct, reliable and effective.