Laboratory method for three-dimensional scour pit reconstruction based on laser scanning

Monopile foundations are widely adopted in the offshore wind industry due to their structural simplicity, high bearing capacity, and broad applicability. This study presents a method for three-dimensional reconstruction of scour pits using a laser scanning technique based on binocular vision. The vision system was calibrated using Zhang's method, and optical corrections were applied to compensate for geometric distortions induced by refraction at the water–air interface. Subsequently, PCA was employed for coordinate alignment, and the LOWESS algorithm was applied to fit the scour depth point clouds merged from camera groups, successfully reconstructing the full scour topography. The accuracy of the proposed method was validated by comparing the reconstruction results with manual point-gauge measurements. Finally, to describe the spatiotemporal evolution of local scour, a space–time state matrix was proposed to analyze the characteristics of representative scour cases.