Air-coupled nonlinear ultrasonic test for reinforced concrete beams

• Main Authors: Ongpeng, Jason Maximino C., Guevarra, Kenneth, Hirose, Sohichi
• Format: text
• Published: Animo Repository 2018
• Subjects: Concrete beams > Testing; Concrete beams—Nondestructive testing; Ultrasonic testing; Civil Engineering
• Online Access: https://animorepository.dlsu.edu.ph/faculty_research/1536
• Institution: De La Salle University

Air-coupled ultrasonic test is a non-destructive test method for investigating damage in material. In this paper, reinforced concrete beams with one 8-mm diameter rounded bar were casted and tested under four-point bending test with water-cement ratio of 40% and 60%. The transducers were placed and focused on the horizontal surface with induced 3mm notch at the midpoint where maximum tension occurred and crack formation was located. Frequency domain waveform was used specifically to analyze second harmonic generation (SHG). There were two metrics used under the SHG, these were: second harmonic amplitude (SHA) and second harmonic ratio (SHR). The SHR proved to be consistent for both water-cement ratio and it behaved increasing as damage in tension increases. © IABSE Conference, Kuala Lumpur 2018: Engineering the Developing World - Report. All rights reserved.