| 摘要 |
PROBLEM TO BE SOLVED: To provide a subsoil exploration apparatus having a simple configuration and enabling both subsoil boring for sampling of the subsoil and standard penetration test for measurement of an N value to be performed by one subsoil exploration apparatus in a short time.SOLUTION: A leader 13 is rotated at a standard penetration test position B, and a boring rod 33 is gently lowered to the perforated bottom of a hole drilled by a boring rod 26. The axial center of the drilled hole (axial center of the boring rod 26) and the axial center of the boring rod 33 at the standard penetration test position are located in a substantially concentric manner. Therefore, the upper end of the boring rod 33 can be struck and an N value can be measured after drilling a subsoil by the boring rod 26 without moving the position of a subsoil exploration apparatus 1, so that the work time can be shortened. |
