Advances in High- Accuracy Three- Dimensional Dynamic Deformation Measurement and its Applications for Large Structures

High-accuracy panoramic three-dimensional (3D) dynamic deformation measurements are of considerable significance for studying the mechanical properties of large or ultra-large structures. As a simple, non-contact, and highprecision full- field deformation measurement technology, three-dimensional digital image correlation ( 3D-DIC) can provide an effective measurement method for large- scale structural deformation measurement. This paper introduces the basic principles of 3D-DIC measurement and presents key technical advancements in the panoramic deformation measurement of large structures with multiple cameras. These advancements include large-scale speckle fabrication, 3D calibration of large field- of-view, coordinate unification of multi-camera systems, and real-time calibration of camera extrinsic parameters. Furthermore, this paper presents practical applications of high- accuracy 3D dynamic deformation measurements for large structures in civil engineering and aerospace engineering fields, such as the assessment of the cassette structure in seismic shaking table tests, panoramic high- speed deformation measurement of suspension cable dome structures in progressive collapse tests, and panoramic deformation measurement of cabin structures of launch vehicles in load tests. Using highaccuracy 3D dynamic deformation measurements for large structures provides a reliable experimental method for seismic performance analysis, mechanical modeling of large structures, and in-depth study of failure mechanisms.