Dynamic Behavior of Gravity Retaining Walls with Coral Sand Backfill under Earthquakes:Shaking Table Tests

The retaining walls in coral sand sites are inevitably threatened by earthquakes.A series of shaking table tests were carried out to study the seismic stability of gravity retaining walls with coral sand backfill.Parallel tests with quartz sand were performed to compare and discuss the special dynamic properties of coral sand sites.The results show that the acceleration difference between the retaining wall and the coral sand backfill is 76％-92％that of the quartz sand,which corresponds to the larger liquefaction resistance of coral sand compared with the quartz sand.However,the horizontal displacement of the retaining walls with coral sand backfill reaches 79％of its own width under 0.4g vibration intensity.The risk of instability and damage of the retaining walls with coral sand backfill under strong earthquakes needs attention.