Pre-stack migration imaging (PMI) method,which is used in geophysical exploration by the performance of single side detection and visually display,can be used to identify the location,orientation,and severity of damages in concrete structure.In particular,this letter focuses on the experimental study by using a finite number of sensors for further practical applications.A concrete structure with a surface-mounted linear PZT transducers array is illustrated.Three types of damages,horizontal,dipping and V-sha...