预应力技术在钢结构抗侧体系中的创新与研究

Inovation and research of prestress technology in lateral system of steel structures

预应力技术具有很强的创新潜力,目前预应力技术已广泛应用于横向结构体系,但在竖向抗侧体系中的研究和应用较少.文中介绍了几种预应力技术在钢结构抗侧体系中的应用.着重介绍巨型钢框架-预应力复合支撑体系,该体系中刚性支撑与预应力拉索组合形成封闭、自平衡的复合支撑系统;对其进行三维有限元模型数值分析,包括竖载、水平风载静力分析及地震动时程分析,结果表明复合支撑有效增加了巨型框架的抗侧刚度,缓解了巨型桁架节点、构件受力集中现象.同时介绍了预应力巨型支撑-钢框架结构、预应力门式刚架及预应力梁柱连接.

The prestress technology has strong innovation potential for structures.At present,it has been researched and applied widely in span structures.However,research work for vertical lateral system is few.This paper introduced several steel structures and nodes with the prestress technology,which were all original.It focused on the mega steel frame with composite brace,in which the composite brace was combined with the rigid splayed lattice brace and the flexible prestress cable.The composite brace was self-balancing.Furthermore,this paper established a 3D model of the new mega structure with suspended sub structure,and analyzed its mechanical performance under the vertical static load,the horizontal wind and dynamic time-history with nonlinear finite element method.The results indicate that the self-balancing composite brace can effectively mitigate the stress concentration in mega columns,mega beams and nodes,as well as enhance the lateral stiffness of the mega frame.The prestressed-mega-brace-frame structure,the prestressed portal frame and the prestressed connection were introduced too.