PURPOSE: To secure necessary amount of soil for covering by a method in which a guide bar is fixed over the whole length to insides of both sides in close contact with an impaction receiving plate 4 of a resistance plate 1 on one side of a foundation A, and an auxiliary resistance plate is inserted into the foundation A under guidance of the guide bar.

CONSTITUTION: A foundation A consists of a semi-circular resistance plate 2 having a connecting skirt 2 on its longitudinal both sides, an impaction receiving plate 4 having a groove 5 to be fitted with a driving tool, and guide bars 6 set over whole length on the insides of both sides in close contact with the plate 4 of a resistance plate 1 on one side. The auxiliary resistance plate 7 has a <- shaped cross section, a size enough to be slidably touched by the guide bar 6, and a length enough to obtain a soil covering amount larger than the foundation A. The driving tool is contacted with the plate 4, the foundation A is placed on the ground, the resistance plate 7 is placed in the foundation A and projected from the lower side of the foundation A, and the soil covering amount is secured.