Seismic damage mechanism of multi-anchored reinforced soil walls with high ground water level

Abstract

Generally, the performance of reinforced soil retaining walls against earthquake is known as higher than other non-reinforced soil structures. Some of the structures are suffered from the decreased efficiency of drainage facilities due to insufficient designs or constructions. The reinforced soil structures were often damaged during earthquakes due to the effects of seepage induced by rainfalls. In order to clarify the mechanism of the damage, it is necessary to examine seismic behavior of reinforced soil walls under the infiltrated rainfall. In this study, a series of centrifuge model tests on the multi-anchored reinforced soil retaining wall were conducted to investigate the deformation mechanism due to earthquake. As a results, high seismic performance of reinforced retaining soil walls was recognized even during seepage flow. In the case of the reinforced soils retaining walls with very loose compaction of backfill, however, the large deformation leading to ultimate critical state occurred. The test result also shows the unique behavior of reinforced region that moved integrally. This implies that the reinforced region has been behaved as if it became one mass, and this behavior make this structure increase seismic performance. It was clarified that design and construction of the backfill equipped with drainage facilities are important to maintain the stability of the soil retaining walls during earth quake with high ground water level.