Probabilistic performance assessment of gravity-designed steel frame buildings using buckling-restrained knee braces

作者：Shin Jiuk; Lee Kihak^*; Jeong Seong Hoon; Lee Jaehong

来源：Journal of Constructional Steel Research, 2015, 104: 250-260.

DOI：10.1016/j.jcsr.2014.10.019

• Small-scale building
• Seismic retrofit scheme
• Fragility contour method
• 2-Story gravity-designed steel frame building
• Buckling-restrained knee brace

In building design codes, buildings having less than 3 stories and a floor area less than 1000 m(2) are generally defined as small-scale buildings, and these are generally exempted from seismic requirements. To prevent potential loss of life and economic damage in the event of an earthquake, such buildings should be retrofitted so as to conform to current seismic design codes. In this study, a seismic retrofit scheme using buckling-restrained knee brace (BRKBs) was developed for a 2-story non-seismic gravity-designed steel frame building using the fragility contour method. To develop an effective retrofit scheme using BRIG for this building, 75 types of BRKB analytical models were used to achieve the desired performance levels and analyzed. Then, the seismic performance of the building before and after the retrofit was evaluated using the fragility contour method, and the improvement in the performance level of the probability against the structural limit state, such as component failures and structural collapse, was investigated. Based on the analytical studies, the most effective BRKB model for the retrofit scheme was proposed based on various scenarios in terms of the weight of the developed BRKB models. This study shows that the fragility contour method can be used for rapid evaluations and should be an effective tool for structural engineers to perform the seismic retrofit of buildings.

• 出版日期2015-1