Concrete and Masonry NDT

Assessing the compressive strength of in-place concrete is often necessary for various construction projects, however, the traditional method of testing concrete cores extracted from a structure can be time-consuming and potentially harmful to the structure, particularly when many structural members need evaluation. As a result, alternative methods such as non-destructive testing (NDT) minimize the need for coring and cause no damage or only limited damage.  

NDT is employed to assess the quality, integrity, and durability of these materials, as well as to identify any defects, flaws, or potential weaknesses. Concrete NDT typically involves the inspection of reinforced concrete structures such as buildings, bridges, dams, and tunnels and many factors are considered in developing a non-destructive testing program for concrete and masonry such as thickness of the test material, access to one or both sides, and the objective of the testing program.  Our NDT professionals understand the strengths and weaknesses of various NDT methods, and typically develop a program of multiple NDT methods to answer our client’s questions.  

Common NDT methods used for concrete and masonry include: 

• Ground Penetrating Radar (GPR) 
• Infrared Thermal Imaging (IR) 
• Ultrasonic Pulse Velocity (UVP) 
• Radiography 
• Ultrasonic Tomography 
• Slab Impulse Response (SIR) 

Supplemental Test Methods

Non-destructive methods do not provide definitive strength values which are frequently necessary for design.  The following test methods may be used to determine the in-place strength of existing concrete or the bond strength between an overlay and substrate: 

• Cut and Pull Out (CAPO) 
• Bond Testing 
• Shear Strength by Torque Method