ABSTRACT

Japan is one of the most seismically disastrous countries in the world and has oen suered signicant damage from large earthquakes. e earthquake disaster prevention technology for highway bridges has been developed on the basis of such extensive damage experiences since the 1923 Kanto earthquake. Various provisions for designing bridges have been developed to mitigate damage due to the instability of soils such as soil liquefaction and the insucient strength and ductility of structural members. Furthermore, design detailing including unseating prevention devices was introduced to prevent the total collapse of bridges against a large earthquake exceeding the design level. With development and improvement of seismic design provisions, damage to highway bridges caused by the earthquakes had been decreasing dramatically in recent years.