Abstract: Calcareous sand is a special marine geotechnical sediment, which has unexpected physico-mechanical property due to its composition and structure. Study of dynamic characteristics of saturated calcareous sand under explosion has important theoretical and practical significance. This paper aims at studying attenuation rules of earth pressure, pore pressure and vibration acceleration in different relative density calcareous sands due to explosive load through model experiment. Results show that explosive wave attenuates as the distance increases in saturated calcareous sand, and attenuation speed decreases as the distance increases. Explosive wave attenuates slower as relative density increases; excess pore pressure due to explosion reaches the peak value within 10 to 30 millisecond, and about 90 percents excess pore pressure dissipates in the previous 3 minutes; since delay explosion is used in this experiment, dynamic behavior of saturated calcareous sand is more intensive because of explosive wave overlap. Calcareous sand has strong absorption and attenuation effect for P-wave due to its particle breakage characteristics, and about 25% explosion energy loosed to form crush zone, compression zone and damage zone.

Key words: calcareous sand, dynamic behavior, explosion experiment, attenuation rule