Nondestructive Concrete Characterization System
Abstract
NCSU played a critical role in casting concrete blocks with compressive strengths ranging from 7.6 ksi to 26.8 ksi after curing in the CFL environmental chamber. NLAD was able to demonstrate the ability of the NLA RECON(Trademark) to detect wall thickness and estimate concrete compressive strength within the accuracy required by the U.S. Army, locate steel reinforcing bars, and identify the presence of steel fiber reinforcement. The thickness of all sides of each concrete block was measured using the P-wave velocity obtained from the pitch-catch method of ultrasonic testing in conjunction with the resonance frequency. All results were within the specified tolerance of 1 ft. The compressive strength of the concrete blocks was measured by measuring the P-wave and S-wave time of travel with the pitch-catch method of ultrasonic testing. All results were within the specified tolerance of 3 ksi. The presence and approximate location of internal rebar was detected successfully using the pitch-catch method. When testing over a bar, the returned signal would increase greatly, indicating a strong reflection had occurred. Metallic fibers were detected magnetically. Synthetic fiber was not detected; however, higher frequency transducers might enable detection.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 20, 2013
- Accession Number
- ADA586704
Entities
People
- Aldo Bellotti
- Rudolf Seracino