The piezoelectric impedance transducer is widely used for damage detection and identification of civil/mechanical infrastructure using the electro-mechanical impedance technique, in which structural equivalent impedance is derived from the piezoelectric coupled admittance signatures of the lead zirconate titanate (PZT) patches bonded to the structure via adhesive bond. In Piezo-elastodynamic model, the bonding layer has significantly altered the overall performance of the electro-mechanical admittance signature. This paper presents the evaluation and detection of structural damage using continuous shear lag model. A three-dimensional (3D) finite element model (FE) has developed to find the effective point-driven impedance, which further integrate into continuum shear lag model to obtain the piezoelectric coupled signature. The continuum-based signatures for different damage model were compared with existing impedance-based shear lag model to highlight the efficiency and accuracy of continuum model towards damage detection process. The simulated signatures were compared with experimental signature, found satisfactory matching. From this study, it has found the continuum strain has more sensitive towards different damage levels in the host structure. © 2021, Krishtel eMaging Solutions Private Limited.