A repair quality control with elastic waves based methods vs. substrate quality

An adhesion in repair system is one of the most important factors that affect the repair efficiency. The elaboration of reliable nondestructive method for an adhesion mapping is one of the most important tasks. A majority of NDT methods mentioned in EN 1504-10 and ACI Concrete Repair Manual for assessment of concrete structures are based on propagation of stress waves. However, these investigations are rarely focused on evaluation of bond strength. Repair system is difficult to test with NDT methods because of many factors influencing stress wave propagation. In this paper the effect of a quality of concrete substrate on propagation of stress waves in repair system and their influence on possibility of estimation of the bond strength is discussed.