It is also pointed out that the topological structure near leading edge depended on not only the gap size but also loading of cascade and thickness of inlet boundary layer.

According to the causation, foundation depth and location, the soft foundation can be treated using the methods of surface layer treatment, displacement, loading and vertical drainage.

The purposes of the tests are to determine, the consolidated condition of this layer in natural state, the in-situ shear strength and the variation of shear strength under loading and unloading.