Study on the behavior of a one way eccentric braced frame under lateral load

Abstract

The present research focuses on studying the structural performance of reinforced concrete frame structures with one-way eccentric bracing due to lateral load, including stress–strain relationships and bending capacity. The effectiveness of various eccentricities was also inspected. In this experimental study, three reinforced concrete frames with simple beam-columns were investigated. Due to the limited number of tested specimens, this research cannot have a general validity and the main point is to clarify the advantages and disadvantages of eccentric one-way braces with respect to concentric ones. The dimensions, including the 70 cm height and 100 cm length were investigated. The first model, without eccentricity (called CBF), was used as the basic model. Meanwhile, other models were given eccentricities of 15 cm and 30 cm on the upper side (called EBF-15 and EBF-30). The main reinforcement was O6 mm with O4–150 stirrups. The load was measured using a load cell applied laterally. The results state that EBF-15 has a similar result to the maximum load and displacement of the CBF. However, the stress–strain relationship shows that EBF-15 has a larger strain. In addition, the largest moment capacity, 30.27 kN m, is shown in CBF, while EBF-15 and EBF-30 are 30.20 kN m and 14.41 kN m, respectively. Therefore, the smaller eccentricity of EBF has a close advantage to CBF and can be an alternative to change concentric bracing to eccentric due to difficulty in applying to a real structure.