基于整体承载极限状态的钢结构可靠度设计方法及其在门式钢刚架设计中的应用

Reliability based integrated design of steel structures and its application in design of portal frames

本文提出了基于整体承载极限状态的钢结构可靠度设计思路。这种思路建立在钢结构整体非线性分析和验算的基础上,并确保结构整体而非构件的可靠度水平,使结构整体的实际可靠度水平尽可能地接近于设计的目标值。本文针对门式钢刚架结构建立了一套实现这种设计的方法,包括结构整体非线性分析、结构体系可靠度计算以及实用的设计表达式。通过三个门式钢刚架结构设计实例比较了传统的构件设计方法,不考虑体系可靠度的整体承载极限状态设计方法和本文考虑体系可靠度的整体承载极限状态设计方法的设计结果,说明本文所提出设计思想的先进性。

The methodology of reliability based integrated designs is proposed in this paper for steel structures, which is based on integrated structural nonlinear analysis and structural check, and assures the structural reliability level toward the design aim. To apply this novel method to design of steel portal frames, the integrated nonlinear analysis, the assessment of frame systems and the practical design formats of steel portal frames with tapered members were studied. Three various design methods, including the traditional member check LRFD, the integrated structural design taking no account of system reliability and the integrated structural design in consideration of system reliability, namely the method proposed in this paper, were compared in the design examples.