Authors: Mitsuyoshi Akiyama; Yoshikazu Takahashi; Yoshiya Hata; Riki Honda
Addresses: Department of Civil and Environmental Engineering, Waseda University, Building 51-16-09, 3-4-1 Okubo Shinjuku-ku, Tokyo 169-8555, Japan ' Department of Civil and Earth Resources Engineering, Kyoto University, Kyodai-katsura, Nishikyo-ku, Kyoto 615-8540, Japan ' Division of Global Architecture, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871, Japan ' Department of International Studies, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5, Kashiwanoha, Kashiwa, Chiba 277-8563, Japan
Abstract: The Mw 7.0 Kumamoto earthquake occurred at 1:25 a.m. (local time) on April 16, 2016, in the Kumamoto Region of Kyushu Island, Japan, after the large foreshock on April 14. This paper presents the damage to bridges during the 2016 Kumamoto earthquake. Field investigations conducted after this earthquake proved the effectiveness of upgrades to seismic design codes and seismic retrofits. Meanwhile, as-built bridges over the Kyushu Expressway collapsed, preventing traffic passage. Some bridges designed according to design codes published after the 1995 Hyogo-ken Nanbu earthquake (i.e., Kobe earthquake) were severely damaged. In addition, several bridges were washed away or collapsed owing to the landslides caused by the strong ground motion. Lessons from the 2016 Kumamoto earthquake based on field investigations of damage to bridges are discussed herein. It indicates the necessity to establish the concept of 'anti-catastrophe' in the design code of bridges under multi-hazard circumstances, taking into consideration the occurrence of extreme events which are rare but can cause severe consequences.
Keywords: Kumamoto earthquake; bridge damage; anti-catastrophe; landslides; seismic design codes; seismic retrofit; earthquakes; bridges; Japan.
International Journal of Earthquake and Impact Engineering, 2016 Vol.1 No.3, pp.225 - 252
Received: 06 Aug 2016
Accepted: 27 Aug 2016
Published online: 19 Jan 2017 *