预应力张拉引起的现浇结构支架加卸载效应研究

Study on Load-unload Effect of the Cast-in-situ Structural Stents Caused by Prestress Tension

近年来纵横梁格体系在桥梁工程中得到了广泛应用,但是横梁内曲线预应力的张拉会导致部分支架受力过大。首先分析了预应力荷载下支架加卸载效应的力学原理,提出了支架加卸载系数的概念和计算方法;然后以赵家沟大桥纵横梁格结构为背景,研究了预应力荷载下刚性支架、刚柔混合支架的加卸载效应规律,使得施工支架设计更科学,提高了支架的安全性。

Crossbar girder grillage system has been widely used in bridge engineering in recent years,but the curve prestressed tension in girder can lead to too large force of partial stents. Firstly,this paper analyzes the mechanics principle of prestressed stents under load-unload effect,puts forward the concept of load-unload coefficient and the calculation method of stents. And then based on the background of the crossbar girder grillage structure of Zhaojiagou Bridge,load-unload effect rule of the rigid support,firm soft hybrid scaffold under prestressed load is studied,the construction stent is designed more scientific and the safety of the stent is improved.