METHOD FOR MEASURING SHEAR WAVE VELOCITY IN GROUND DEPTHWISE DIRECTION

摘要

PROBLEM TO BE SOLVED: To obtain a shear wave velocity of a ground where a foundation ground is shallow or a seam is interposed. SOLUTION: A plurality of measurement point blocks 10 with piezoelectric vibrators 12R and 12S are buried via a predetermined distance along a depthwise direction of a ground 2 where velocity logging is conducted. A pair of opposite piezoelectric vibrators of the measurement point blocks 10 arranged adjacent to each other in the depthwise direction are made an oscillation part 12S and an oscillation reception part 12R. A shear wave oscillation generated from one piezoelectric vibrator 12S is propagated in the ground 2 between the measurement point blocks. A wave reach time in the ground after the oscillation is generated before the oscillation is detected by the piezoelectric vibrator of the opposite oscillation reception part 12R is measured. The reach time is measured sequentially between the measurement point blocks of a plurality of pairs. A shear wave velocity of each pair of the measurement time blocks 10 is calculated.