Review of Non-destructive Testing Methods Used for Structural Safety Assessment of Civil Structures

Non-destructive testing (NDT) method plays a significant role in the qualitative assessment of civil engineering structures. NDT is defined as the method of inspecting, monitoring and evaluating the strength properties of various types of civil engineering structures without damaging the structure. It is a very safe, fast, cost-effective, and efficient method for assessment of properties of a material. NDT methods are based on the assumption that certain physical and chemical properties of a material can be linked to structural strength and durability. There is a phenomenal rise in construction activities in the field of civil engineering in the recent few years. Testing and quality control are essential at various points throughout the life of construction to ensure its safety. Most significant structures, such as buildings, bridges, and dams, are subjected to extreme stress conditions all the time, and their performance is likely to alter over time. As a result, NDT methods must be used to examine the structural safety of these structures. In the present paper, the most commonly used NDT methods such as rebound hammer, ultrasonic pulse transmission, impact echo, and resonance frequency test methods used for assessment of quality of various types of civil structures have been discussed and illustrated. The fundamental principles of these methods are also explored in regard to their potential.