Hybrid test study of an RC frame retrofitted by BRBs
Qie Yi1,2 Du Chunbo1,2 Wang Tao1,2
1. Key Laboratory of Earthquake Engineering and Engineering Vibration, Harbin 150080, China;
2. Institute of Engineering Mechanics CEA, Harbin 150080, China
摘要消能减震技术自提出以来逐步得到了广泛应用，在结构加固方面也有较好的表现。屈曲约束支撑（BRB）作为一种结构简单、性能可靠的耗能构件，已经在这一领域中得到了广泛应用。然而，在欧洲规范EuroCode8中却并未对其设计做出明确规定，从而在一定程度上影响了BRB在相关地区的应用。鉴于此，E. M. Marino等人针对钢结构提出了一种建立在EC8框架下的BRB设计方法，并将其推广至RC结构加固领域。基于上述设计方法，对一意大利非设防RC框架结构进行了加固设计，并使用子结构混合试验技术对结构加固前后抗震性能进行了试验验证。试验中使用一条基于欧洲规范生成的人工波在0.1g、0.2g、0.35g和0.45g下对结构进行拟动力加载，试验子结构取为首层边跨，剩余部分为数值子结构。试验表明，使用该方法加固的框架，层间位移角有了明显减小，其竖向分布也更为均匀，结构抗震性能得到了提升。试验结果说明，对于此RC框架的加固设计是有效的，该设计方法对于RC框架的抗震加固也是有效的。
Abstract： Since first brought up, energy dissipation techniques have been widely used and have good performance in structure rehabilitation. As a type of energy dissipation device with simple configuration and stable performance, Buckling-Restrained-Braces (BRBs) have been widely used in this field. However, there’s no specific provisions about the application of BRBs in EuroCode8, which in some way hampers the application of BRBs in related areas. Considering this, E. M. Marino et al proposed a design procedure for BRBs used in steel structures under the framework of EuroCode8, and later on extended it into RC structure rehabilitation. Using this design procedure, an RC frame located in Italy was retrofitted, and a hybrid test study was conducted to verify its performance before and after rehabilitation. During the test, an artificial ground motion was used at PGA of 0.1g, 0.2g, 0.35g and 0.45g. The test substructure is the side span at the first story of the frame and the rest of the frame serves as the numerical substructure. The test shows that the inter story drifts of the frame retrofitted using this procedure are significantly reduced and their distribution is more even. The results show that the rehabilitation of the RC frame is effective, and the design procedure is also effective on rehabilitation of RC frames.
