用可靠度理论确定屈曲约束支撑钢框架的设计原则

Determination of Design Principle of Steel Frames with Buckling Restrained Braces using Reliability Theory

根据同济大学采用国产低碳钢Q195、Q235与宝钢新开发的低屈服点钢BLY160、BLY225研制的两种型号屈曲约束支撑(TJ-I型与TJ-II型)的大量试验结果,应用统计分析与可靠度理论,确定了屈曲约束支撑钢框架的设计原则。给出了具有明确概率意义的,在使屈曲约束支撑达到其极限承载力的外荷载下,框架柱、梁的内力与其设计承载力的比例极限。可保证在罕遇地震作用下,屈曲约束支撑能充分发挥其抗震耗能作用,同时框架柱、梁的可靠度指标β分别不低于3.2与2.7,为国产屈曲约束支撑在抗震工程中的应用提供参考。

Based on the test achievements of two types of domestic buckling restrained braces（ TJ-I type and TJ-II type） developed by Tongji University, which adopted domestic low yield point steel Q195 ,Q235 and newly made low yield point steel BLY160,BLY225 by Baosteel company, the design principle of steel frames with buckling restrained braces is determined by using statistical analysis and reliability theory in this paper. The limit rations of internal forces of frame columns and beams to their corresponding design load bearing capacities under the actions, which cause buckling restrained braces to arrive at their ultimate load bearing capacities, are proposed with definite probability meanings. It can guarantee that buckling restrained braces will fully realize their aseismic consumed energy ability under severe earthquakes and the reliability indices // of columns and beams are not lower than 3.2 and 2.7, respectively. The research result can provide reference for the application of domestic buckling restrained braces in aseismic engineering.