Intrinsic Response Control of Moment-Resisting Frames Utilizing Advanced Composite Materials and Structural Elements

摘要

This paper reports on a research project aimed at investigating the response mechanism of a composite moment-resisting frame system with self-centering and energy dissipation capabilities. The suggested configuration of a particular composite beam and column members in a portal frame structure, serving as a simplified example of a moment-resisting frame system, can accommodate relatively large, inelastic deflections of the beam without formation of plastic hinges at the column bases. The combination of engineered cementi-tious composites (ECC) and fiber-reinforced polymers (FRP) reinforcement results in column elements with relatively high flexural strength and sufficient elastic deflection capacity to permit frame sway and prevent the formation of a collapse mechanism due to lateral loading. The load-deformation response is primarily influenced by an intrinsic transition mechanism of the relative flexural stiffness of beam and column members, triggered by the formation of plastic hinges in the beam. This concept is theoretically outlined and experimentally verified by tests using small-scale frame specimens under reversed cyclic loading conditions. Furthermore, the response of the tested specimens is analytically derived and compared with experimentally obtained data. The spectrum of responses obtained with this suggested configuration demonstrates the potential to design this configuration for a specific bilinear system behavior.