01616182

Component

https://doi.org/10.3141/2592-14

Recent developments in ultrasonic testing hardware, such as air-coupled sensors and multielement shear wave dry-point contact arrays, have brought about a new capability to image the interior of reinforced concrete structures. Data acquired from air-coupled transducers are often reconstructed by using tomographic algorithms, especially when a through-thickness configuration is used to collect data. Data acquired from multielement shear wave arrays are normally reconstructed with the synthetic aperture focusing technique (SAFT), under which the data are collected by using a one-sided pitch-catch configuration. Both approaches are helpful in characterizing full-scale reinforced concrete structures, although each produces a different type of image with distinct characteristics. The differences between the two test methods and data inversion schemes are investigated. Ultrasonic data are collected from a full-scale reinforced concrete column specimen by using air-coupled P-wave transducers and a multielement shear wave array unit. The through-thickness P-wave data are interpreted through tomographic inversion and multielement shear wave data through SAFT reconstructions. The sample column contains embedded artificial defects, including Styrofoam and precracked concrete blocks. The results indicate that both ultrasonic methods produce meaningful internal images with different perspectives. The tomographic reconstructions are insensitive to small cracks and the presence of internal steel bars. The SAFT reconstructions are limited by energy penetration into the structure. On the basis of the comparison study, appropriate applications of ultrasonic imaging tests for each method are suggested.

01594663

16-6059

English

pp 126-135

2016

Transportation Research Record: Journal of the Transportation Research Board

9780309441360

Print

Figures; References

Reinforced concrete bridges; Ultrasonic tests

Imaging systems

Bridges and other structures; Construction; Design; Highways

TRIS, TRB, ATRI

Nov 10 2016 11:03AM

• Advances in Fiber-Reinforced Polymer Composites in Transportation Infrastructure
• Assessment of Concrete Structures Affected by Alkali–Silica Reaction and Freeze–Thaw by Use of Ultrasonic Surface Wave Method
• Design of Short Reinforced Concrete Bridge Columns Under Vehicle Collision
• Effect of Overweight Trucks on Bridge Deck Deterioration Based on Weigh-in-Motion Data
• Evaluation of AASHTO Suggested Design Values for Reinforced Concrete Bridge Piers Under Vehicle Collisions
• Experimental and Numerical Studies on Flexural Behavior of Ultrahigh-Performance Concrete Panels Reinforced with Embedded Glass Fiber-Reinforced Polymer Grids
• Extreme Vehicle Loads on Bridges: Evaluating and Regulating Farm Equipment in Wisconsin
• Flexural Behavior of Pultruded Hybrid Fiber-Reinforced Polymer I-Beams with Bonded-and-Bolted Splice Joints
• Hillsborough River Bascule Bridge Vibration and Rehabilitation
• Influence of Modeling Decisions on Three-Dimensional Finite Element Analysis of Two Existing Highway Bridges Subjected to Lateral Spreading
• Joint Detailing Between Double Tee Bridge Girders for Improved Serviceability and Strength
• Low-Damage Posttensioned Segmental Bridge Columns with Flexible End Joints for Seismic Accelerated Bridge Construction
• Performance Evaluation of Longitudinal Ultrahigh-Performance Concrete Closure Pour Connection for Use in Modular Bridge Construction: Pairwise Comparison of Capacity and Ductility at Failure Limit State
• Performance of Pipe Extender–Shear Key at In-Span Hinges of Multiframe Bridges
• Practical Implementation of Stability Bracing Strength and Stiffness Guidelines for Steel I-Girder Bridges
• Structural Redundancy of Prestressed Concrete Box Girder Bridges
• Tunnel Operations, Maintenance, Inspection, and Evaluation Manual, 2015: Practical Implications for Fire Protection and Life Safety Systems