NDT Assessment, and Repair of Concrete Basement Wall

Carrasquillo Associates (CA) assessed the condition of a 22 in. thick reinforced concrete basement wall and pilasters during construction after irregularities were observed on the surface of the concrete wall. CA determined the extent of the deficiencies and developed a repair protocol for the wall. CA’s investigation of the wall included a visual survey, non-destructive testing (NDT) using ultrasonic echo 3D tomography, and concrete core sampling for visual examination and compressive strength testing. CA non-destructively scanned the wall using ultrasonic echo 3D tomography, a method that uses ultrasonic shear waves to locate internal defects, reinforcement, and the back surface of the concrete. The majority of the NDT testing data did not indicate the presence of internal defects within the wall. Verification cores and compressive strength testing from several of these areas confirmed the absence of internal defects and/or low strength concrete. At CA’s recommendation, the project team approved the repair of the wall.