Seismic Risk Assessment of Existing Low-rise Reinforced Concrete Buildings in Korea

Abstract

Countermeasures against earthquake disasters such as the seismic capacity evaluation and/or retrofit schemes ofbuildings, especially existing low-rise reinforced concrete buildings, have not been fully performed since Korea had not experiencedmany destructive earthquakes in the past. However, due to more than 1200 earthquakes with low or moderate intensity in theoff-coastal and inland of Korea during the past 20 years, and due to the recent moderate earthquakes in Korea, such as the 2016Gyeongju Earthquake with M=5.8 and the 2017 Pohang Earthquake with M=5.4, the importance of the future earthquakepreparedness measures is highly recognized in Korea. The main objective of this study is to provide the basic information regardingseismic capacities of existing low-rise reinforced concrete buildings in Korea. In this paper, seismic capacities of 14 existing low-risereinforced concrete public buildings in Korea are evaluated based on the Japanese Standard for Evaluation of Seismic Capacityof Existing Reinforced Concrete Buildings. Seismic capacities between existing buildings in Korea and those in Japan is compared,and the relationship of seismic vulnerability of Korean buildings and Japanese buildings damaged due to severe earthquakes arealso discussed. Results indicated that Korean existing low-rise reinforced concrete buildings have a narrow distribution of seismiccapacities and they are relatively lower than Japanese buildings, and are also expected to have severe damage under the earthquakeintensity level experienced in Japan. It should be noted from the research results that the high ductility in Korean existing low-risebuildings obtained from the Japanese Standard may be overestimated, because most buildings investigated herein have the hoopspacing wider than 30 cm. In the future, the modification of strength and ductility indices in the Japanese Standard to propose theseismic capacity evaluation method of Korean buildings is most needed.