Seismic performance evaluation and design of steel structures equipped with dual-pipe dampers

Dual-pipe damper (DPD) is a metallic yielding device for passive control of structures, introduced recently by the authors. The objective of the current study is to provide guidelines for implementing DPDs in actual steel buildings, evaluate and compare their performance against other metallic dampers. In this study, a representative load-displacement model for DPDs is proposed for the first time, and assessed based on previous experimental cyclic tests. Guidelines for the design of DPD devices are also presented. Three steel moment resisting frames of 5, 10 and 20 stories are designed and then equipped with DPDs of various properties. The responses of the frames to seven earthquake excitations are investigated using dynamic nonlinear time-history analyses. Performance of the DPD devices is then evaluated through various response parameters including the normalized energy ratios. The results prove the effectiveness of the DPD devices in dissipating a considerable portion of the input seismic energy and significantly reducing the non-structural and structural damage. The responses of a 10-story frame equipped with DPDs are compared to those of the frame with TADAS devices. The results show that the structure equipped with DPD, with its unique secondary hardening portion in force-displacement, results lower structural and non-structural damage compared to TADAS.