Steel Reinforced Concrete Structures in 1995 Hyogoken-Nanbu Earthquake

Abstract

This paper provides a summary of typical damages inflicted on steel reinforced concrete (SRC) structures in Japan, during the 1995 Hyogoken-Nanbu earthquake. The paper is based on observations made by the writers during their visits to the damaged areas. SRC structures are a class of composite structures that have been used in Japan for over 30 years. Research on SRC building components dates back to the 1930s. There was a close correlation between the age of the structures and the observed damage. A majority of the damage was inflicted on SRC structures constructed prior to 1970. However, damage to newer SRC structures was also observed. Typical damage was related to (1) large tie spacing in columns; (2) base plate details; (3) vertical discontinuity in building stiffness; and (4) foundation-related failures. Additionally, the use of 90° hooks, even in conjunction with close tie spacing, resulted in inadequate seismic performance.