中文摘要：

It has been reported that when a loosely packed column of sat-urated sand in a vertical cylindrical container is shock loaded axially by droppingto the floor,large horizontal cracks initiate,grow and eventually fade away in thesand as it settles under gravity.This paper shows that a similar phenomenon canalso be observed when shock loading is replaced by forcing water to percolate upwardthrough the sand column.It is believed that our result sheds further light on thephysics of formation of these cracks.

英文摘要：

It has been reported([1]) that when a loosely packed column of saturated sand in a vertical cylindrical container is shock loaded axially by dropping to the floor, large horizontal cracks initiate, grow and eventually fade away in the sand as it settles under gravity. This paper shows that a similar phenomenon can also be observed when shock loading is replaced by forcing water to percolate upward through the sand column. It is believed that our result sheds further light on the physics of formation of these cracks.