Pump damage in the Hanshin earthquake

摘要

There was a severe earthquake in the southern area of Hyogo prefecture in Japan on January 17,1995. In this paper the damage to pump facilities caused by the earthquake, based on field investigation results in the Hanshin (Osaka-Kobe) area is reported. In particular a lot of damage was reported in the pumping facilities for sewage or drainage of storm sewage. This paper also presents recommendations for aseismic design of pump facilities based on the results of the survey. Some of the kinds of damage to pumps were: pump submersion, shaft misalignment, case of pump rotor getting stuck, anchor bolt failure, pump casing cracking, bearing box failure. Most of the damage was fundamentally caused by unequal sinking of the building foundation. The damage to the pumps was mainly caused by deformation or collapse of building structures, or by excessive forces to be exerted on the pumps by the piping. In order to prevent damage to pumps by earthquakes, a study of the earthquake resistance of the whole pumping facility including the pump itself should be made, and appropriate countermeasures and action taken.