Dynamic compaction (DC) is a typical compaction method by impact energy. DC compact the soil by dropping a temper from a certain height to the ground. The dropped temper generates instantaneous impact energy to the ground, which shall significantly compact the granular soil in a very short time. The most effective part of such impact energy is the vertical energy which will be decreased along depth. Generally speaking, DC is most effective and economical when the target soil is not deep than 6 m.

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