| 摘要 |
PROBLEM TO BE SOLVED: To provide an elastic wave speed-measuring device for easily and reliably mounting and collecting a sensor into a hole in an elastic wave speed measurement utilizing a leaf spring. SOLUTION: An elastic wave speed-measuring device 1 measures an elastic wave speed in a groove hole 20 being provided in the ground for judging to see whether rockbed around an object to be constructed is appropriate or not in such underground civil construction as a tunnel. The measuring device 1 is provided with a sensor part 10 with a sensor 6 such as a piezoelectric element for measuring the elastic wave speed, a leaf spring 2 for pressing the groove hole to an inner wall and fixing the sensor into the groove hole due to its urging force, a lead spring-mounting member 3 such as a hollow pipe that fixes the leaf spring and is long in the longitudinal direction, leaf spring mounting tools 5a and 5b that fix both the end parts of the leaf spring to the leaf spring mounting member and at the same time moving at least one of them along the longitudinal direction of the leaf spring-mounting member, and a travel control means for moving the leaf spring-mounting tool 5b that can be moved from the outside of the groove hole. |
