Journal of Natural Disaster Science

AN ASSESSMENT OF TIME-DEPENDENT EARTHQUAKE EFFECTS ON A HOUSEHOLD IN TERMS OF LIVING STANDARDS

Yutaka OHTA
Professor, Earthquake Res. Inst., University of Tokyo
and
Shigeyuki OKADA
Research Associate, Faculty of Engineering, Hokkaido University

(Received 20 October, 1989 and in revised form 14 February, 1990)

Abstract

Most regional seismic risk assessments have not given a description that includes the causal and time dependent characteristics on damage and restoration processes. To improve seismic risk assessments, we developed a methodology by which time phase risk evaluation was made in terms of "living standards of a household".

The living standards under the critical situation struck by an earthquake were described by a combination of four major factors regarding physical, commodity, family, and economic damages. Damages done to dwellings and lifeline systems were significant elements in the physical factor. Commodity factor relates to shortage of foods, water and other daily goods. Representative elements in the family factor are casualties of the family members. Extraordinary expenses for reconstruction of a dwelling damaged is an important element in the economic factor.

A test run was made for a hypothetical Japanese city with a population of 1 million in order to examine the validity of the method and to provide a comprehensive understanding of the seismic effects on a household.

Key words

seismic risk assessment, dynamic approach, damage and restoration process, household's living standards