LiDAR-Based Design of Canopy Consolidation Systems for Urban Pinus pinea Trees Using Handheld Mobile Laser Scanning and Quantitative Structure Models

This study evaluates whether handheld mobile laser scanning (HMLS) can support the design of canopy consolidation systems for urban Pinus pinea L. trees without climbing into the crown. Fifty stone pines in a historic park in Pistoia (Italy) were surveyed with a SLAM-based handheld laser scanner and assessed with Visual Tree Assessment; five trees were then selected for consolidation design. Tree height, diameter at breast height (DBH), and crown metrics were derived from the point cloud and compared with field measurements, and the scaffold branches were reconstructed as sequences of truncated cones. For each branch, the bending stress generated by self-weight was computed with cantilever-beam theory and compared with the compressive strength of green P. pinea wood; a wind load case and a sensitivity analysis to diameter errors were added. Under self-weight, the safety factor of the vulnerable branches ranged from 1.44 to 37; one branch was below the usual minimum of 1.5 and a second fell to 1.69 under the 27 m/s wind. Anchor positions, rope trajectories, and system classes (4 t or 8 t) were drawn directly on the point cloud. The study is proof of concept: the systems have not been installed, and the mechanical results have not been verified by load tests, but the workflow shows that the data needed for consolidation design can be obtained remotely and non-invasively.