非破壊試験法 (2)

[V-552] Effects of compressive strength and strain on the relationship between surface wave velocity and concrete stress

*篠崎 裕生¹、野並 優二¹、大野 健太郎²、永田 昂大² (1. 三井住友建設株式会社、2. 首都大学東京)

Keywords:prestressed concrete, nondestructive inspection, ultrasonic velocity, creep strain

The ultrasonic velocity of the test specimens in which the concrete stress was gradually increased was measured with the purpose of obtaining basic data to estimate the concrete stress by the velocity using the ultrasonic wave. The test results show that the concrete stress and ultrasonic velocity are proportional to each other, and the effect of compressive strength on the gradient is small, and the effect of rebar on velocity is small by using surface waves. Also, from the measured values after creep deformation, a proportional relationship was also found between strain and ultrasonic velocity.