Akio Kitahara

Risk Management for Urban Planning Against Strong Earthquakes

Publisher Summary This chapter introduces typical types of damage to buildings and the infrastructure subjected to the Hyogoken Nanbu, also called the Hanshin–Awaji earthquake and analyzes statistics on the extent of damage and characteristics of the structures obtained from Ashiya, a city next to Kobe, Japan. The anti-seismic strength of 263 existing reinforced concrete structures were compared with the extent of damage level in terms of when they were constructed. The 1995 Hyogoken Nanbu earthquake, which measured 7.2 on the Richter scale, wreaked havoc throughout the Kobe area, destroying or damaging a large percentage of the infrastructure. The national and private railways between Osaka and Kobe were completely disrupted because of severe damage. In some places close to the mountains, buildings were severely damaged by landslides. The degree of damage seemed to be closely related to the period when buildings were constructed, as evidenced by changed building codes and the material deterioration of wooden houses. The chapter also presents a method of damage estimation in an urban area Kyoto City, subjected to a scenario earthquake that is based on the strength distribution and soil conditions in that area. A method of integrated risk management for future urban planning against strong earthquake damage based on the experience of the Hyogoken Nanbu earthquake also is discussed.