To provide an automatic penetration testing machine capable of precisely detecting a load which is actually applied on a penetration rod.
An automatic penetration testing machine 1 comprises a lifting stage 3 capable of rising and falling along a post which is provided upright, a chuck 5 which is provided to the lifting stage 3 and contains a bearing support for free rotation, a penetration rod 4 that penetrates the ground as the lifting stage 3 falls, and a lifting drive means 8 which is provided to operate the rising/falling of the lifting stage 3 capable of changing a load applied on the penetration rod to a predetermined value by adjusting output torque. An annular washer type load cell 26 is inserted into the penetration rod 4. Distortion is generated upon receiving a thrust load of the penetration rod 4 which acts through bearings 22 and 23, and from the amount of distortion, a thrust load applied on the penetration rod 4 is detected.
SHIMIZU HARUHIKO
YASUEDA MASAAKI
