SUBSURFACE EXPLORATION METHOD AND SUBSURFACE EXPLORATION APPARATUS

摘要

Provided are a subsurface exploration method and apparatus whereby physical characteristics such as the dynamic strength (penetration resistance value) of the subsurface at test depth and the soil quality distinction at each depth can be easily evaluated, and liquefaction strength at any point can be easily measured. According to the present invention, there is provided a subsurface exploration method for exploring the subsurface (t) by driving in a rod (3) having a removable penetrating member (2) at the tip (3a), and causing the penetrating member (2) to penetrate the subsurface (t) in a depth direction. By causing the penetrating member (2) to penetrate the subsurface (t), the amount of penetrating displacement of the penetrating member (2) is measured, the penetration resistance value of the subsurface depth is analyzed from the obtained amount of penetrating displacement, and after the penetrating member (2) penetrates down to a subsurface depth that has been set in advance, the amount of withdraw displacement and a withdraw resistance value are measured by withdrawing the rod (3), physical characteristics including at least a soil quality distinction are analyzed from the obtained measured values and the penetration resistance value, and the liquefaction strength of the subsurface is analyzed from the obtained physical characteristics and the penetration resistance value.