一种新型屈曲约束支撑的研制与试验研究

Invention and experimental study on a new type of buckling-restrained brace

屈曲约束支撑由于具有受压不会屈曲失稳的性质,与含有普通支撑的框架相比,含有屈曲约束支撑的框架具有更好的耗能作用。然而常规屈曲约束支撑的芯材和无粘结材料往往采用特殊材料制成,加工制作成本较高,不利于工程推广使用。为了避免常规屈曲约束支撑存在的上述缺陷,自主研制开发了一种带有缝隙和防滑凸起的新型屈曲约束支撑。着重介绍了这种新型屈曲约束支撑的构造和特点,并对6个支撑试件进行了包括标准加载和循环加载在内的低周反复加载试验。结合试验现象,分析、探讨了支撑的破坏机理。对这种屈曲约束支撑的弹性刚度、塑性刚度、屈服荷载和屈服位移等力学指标进行了测定,并将测定结果与基于双线性模型计算出的理论值进行了比较;同时参照我国规范和FEMA356,探讨了这种屈曲约束支撑的耗能能力。试验结果表明,这种新型屈曲约束支撑各项力学指标实测值与理论值符合较好,耗能能力稳定,满足国内外规范的要求,达到了工程应用的标准。

Because the buckling-restrained braces（BRB） will not buckle under compression other than yield,the buckling-restrained braced frame（BRBF） has better energy dissipation characteristics than the conventional braced frame（CBF）.The steel core and unbonded agent material of the existing BRB are usually made of special material.It makes the promotion of the BRB become hard.In order to avoid the disadvantages of the existing BRB,a new type of BRB with gap and protuberance was invented.The components and features of the new type of BRB were emphatically introduced.The low-reversed cyclic loading test of six BRB including standard loading and low-cycle fatigue loading were carried out.Based on the phenomenon of BRB during the test,the damage mechanism of BRB was analyzed and discussed.The comparison of measured and theoretical mechanics characteristics of BRB,including elastic stiffness,plastic stiffness,yield force and yield displacement was done.And analysis of energy dissipation indexes of BRB based on the Chinese codes and FEMA356 was also done.The test results indicate that the measured mechanics characteristics of BRB agree well with theoretical results and the energy dissipation behavior of BRB is stable.This new type of BRB can meet the requests of existing codes and reach the standard of application.