ON PREVENTING LIQUEFACTION OF LEVEL GROUND USING GRAVEL PILES

In this research, liquefaction tests by impact were performed for both improved ground with a single gravel pile and unimproved ground. We found that surface settlement of improved ground was larger than that of unimproved ground. And we obtained some knowledge of distribution pattern of pore water pressure in the improved ground. On the basis of these test results and some assumptions, we proposed a simplified designing formula for gravel piles against liquefaction during earthquakes. Shaking table tests were also performed in this research to represent that the simplified designing formula was proper from engineering point of view.