ON DESIGN OF EXPRESSWAY EMBANKMENT IN SEISMICALLY ACTIVE AREA WITH EMPHASIS ON LIFE CYCLE COST

This paper addresses the role played by life cycle cost (LCC) calculation in a seismic design of geotechnical structures. The recent trend towards the performance-based design is pushed further to arrive at the optimum design by using the LCC principle. Since geotechnical engineering still has many uncertainties in the LCC calculation, consideration and decision were made to solve each of them. As a research product, an example calculation was made of an expressway embankment whose interruption upon a major earthquake would cause significant damage to the economy. The results show that the indirect loss due to the elongated travel time during the interruption is the most significant source of LCC. Accordingly, it was found that the choice of design specification is affected by, whether a conventional seismic design principle is employed or LCC-based principle is made use of.