A Case Study of Earthquake Resistant Retrofit Design with Economical Braced Steel Frame System for a Primary School

Abstract

This paper makes a case study of an elementary school in Feng-shan District, Kaohsiung City. According to “The handbook of seismic resistant evaluation standard for school buildings” issued by National Center for Research on Earthquake Engineering (NCREE) in 2009, this study analyzes elementary school building adopting braced steel frame retrofit system, conducts seismic evaluation, as well as compares its seismic performance with shear-wall retrofit structure and RC strengthening of columns . If space permits, braced steel frame retrofit system can be applied into school building retrofit scheme; its seismic performance is compared with shear wall and RC strengthening of columns proposals. Adopting shear wall or RC strengthening of columns retrofit would affect main structure system of school building. These constructions will make existing reinforced concrete school building crack, especially old school building whose structure strength is greatly influenced. Therefore, an economic braced portal frame systems are proposed as new way of retrofitting. This paper uses ETABS program to make a seismic evaluation for structural system of the study object. It also compares the research object with commonly-used shear wall retrofit and RC strengthening of columns retrofit, thus to judge whether it meets requirements stipulated in seismic standards issued by NCREE and provide an another alternative scheme for the primary school retrofit construction.