| 摘要 |
PROBLEM TO BE SOLVED: To measure the drainage properties of a road surface during the running of an inspection vehicle loaded with an apparatus for measuring the drainage properties of the road surface. SOLUTION: A signal generator 10 forming a predetermined pulse signal, a speaker 30 converting the pulse signal formed by the signal generator to the pulse sound emitted to a road surface 100, a sound sensor detecting both of the direct sound before arriving at the road surface emitted from the speaker and the reflected sound produced after the sound emitted from the speaker is reflected by the road surface 100 and a signal analyzer 60 calculating the drainage properties of the road surface on the basis of the direct sound and reflected sound detected by the sound sensor are provided. |
