论文部分内容阅读
采用铸造工艺直接加工十字形截面核心的屈曲约束支撑(BRB,Buckling-Restrained Brace),避免在核心部件上直接施焊,可以消除焊接残余应力的影响。通过低周往复加载试验,研究了该类试件的滞回性能、骨架曲线、累积塑性变形、拉压不对称性、等效刚度等。试验结果表明,该类型的屈曲约束支撑可以避免焊接残余应力对试件抗震性能的影响,支撑试验滞回曲线饱满,具有稳定的受力特性,累积塑性变形基本达到200,且拉压不对称系数小于1.3,满足美国AISC钢结构规范的要求。由于铸造用钢有材料上的缺陷,导致试件没有获得较好的低周疲劳性能,但是对低周疲劳性能要求不高的承载型BRB仍具有一定的应用价值。
The casting process is used to directly process Buckling-Restrained Braces (BRB) at the core of cruciform cross-section to avoid the direct welding on the core components, which can eliminate the influence of welding residual stress. The hysteretic behavior, the skeleton curve, the cumulative plastic deformation, the tension and compression asymmetry, the equivalent stiffness and so on were studied by low cycle reciprocating loading test. The experimental results show that this type of buckling restrained brace can avoid the influence of welding residual stress on the seismic performance of the specimen, the hysteresis curve of the brace test is full and has a stable mechanical behavior, the cumulative plastic deformation basically reaches 200, and the tension-compression asymmetry coefficient Less than 1.3, to meet the requirements of the United States AISC steel structure specifications. Due to the material defects of the cast steel, the test piece does not obtain good low cycle fatigue performance, but the bearing type BRB which does not require low cycle fatigue performance still has certain application value.