抄録
The pourpose of this paper is proposing the method that evaluates the risk of stone trouble for floor material. First, the water penetration speed was measured regarding floor stones of several thicknesses through four hours each. Second, I propose the method of the reappearance test that is able to reappear of stone trouble acceleratory. Finally the relations between the penetration speed and the results of the reappearance test were studied and revealed the potentiality of stone trouble.
