FUNDAMENTAL STUDY ON REDUCING SETTLEMENT DURING LIQUEFACTION USING LIGHTWEIGHT CRUSHED SHELL PARTICLES

Abstract

 One of the liquefaction countermeasure methods is the gravel drain (GD) method using highly permeable crushed stone to reduce the amount of excess pore water pressure during liquefaction and to accelerate its dissipation. On the other hand, flat shell piles are more likely to be damaged. On the other hand, shell drain (SD) piles constructed with flat shell particles have been reported to be more effective as liquefaction countermeasure piles than GD piles, because the drainage performance of SD piles is less affected by sand contamination than that of GD piles. In addition, shells are lighter than crushed stone, and the application of SD piles may reduce the amount of post-seismic ground settlement. In order to confirm the effectiveness of SD piles in reducing post-seismic ground subsidence, which is considered to be effective against repeated earthquake ground motions, this study experimentally clarified the effectiveness of SD piles in reducing post-seismic ground subsidence by comparing the amount of ground subsidence after vibration with that of GD piles in 1G field shaking table experiments.