非破壊試験法(2)

[V-384] Relationship between shear wave velocity and excitation frequency in plain concrete specimen exposed outdoors

〇Yuichiro Arai¹, Hiroyuki Sakamoto², Sakae Ushijima¹, Toshio Sato¹, Soushi Mikami² (1.Asunaro Aoki Construction Co.,Ltd., 2.Earth System Science Co., Ltd.)

Keywords:non-destructive test method, ultrasonic shear wave, excitation frequency, shear wave velocity, aging

In this paper, the relationship between the propagation speed of ultrasonic transverse waves propagating in concrete and the excitation frequency was verified using two types of unreinforced concrete specimens having different strengths. As a result of the verification, when the frequency of the ultrasonic shear wave input to the concrete was increased, the phenomenon that the shear wave propagation velocity decreased was observed. It was also confirmed that the rate of decrease in shear wave propagation velocity decreased with increasing concrete strength. These phenomena are the same as previously reported measurement results.