Abstract
The article focuses on a methodology for detecting damage in steel lattice transmission towers based on measurements of their dynamic characteristics. As part of the research, field experiments were conducted on selected towers using accelerometers and ground-based radar interferometry. The collected data were analyzed using modal analysis and compared with the results of validated FEM models. These models were further used to simulate damage, and the resulting changes in modal parameters served to identify structural damage. Methods such as CAMOSUC (Change of Mode Surface Curvature) and techniques based on changes in the diagonal elements of the modal flexibility matrix were tested. The results show that radar interferometry is suitable for fast, contactless measurement of fundamental frequencies. The study provides recommendations for the practical application of these methods in monitoring critical infrastructure.