Remote Sensing Approach to Riprap Slope Inspection
Department: Mechanical Engineering
Advisor: Dr. Michael McGuire
Riprap, or rock fragments, armor many of the upstream and downstream slopes of dams, dikes, and levees. This riprap must be adequately heavy and durable to protect the slope from the erosive forces of wind, rain, and waves. Over time, the riprap can degrade by breaking into smaller pieces, and therefore, periodic inspection is important. Current procedures for inspecting riprap involve a trained dam inspector subjectively evaluating existing conditions. The present study presents an empirical relationship between the surface roughness of three-dimensional (3D) point cloud data captured of the riprap slopes and the median size, D50 of the riprap material, which allows for an objective assessment of rock size. The point cloud data, a dense collection of 3D position measurements, can be generated using lidar or photogrammetry technologies. Field studies are an important component of this project; however, physical sampling of the riprap at the surface of a slope only discloses an estimate of the true particle size distribution. Therefore, a simplified kinematic model of 2D disks was used to test the empirical relation between roughness and rock properties. In addition to numerical simulations, lessons learned from three case studies are presented.
About Travis Shoemaker:
Travis Shoemaker is a senior at Lafayette College studying civil and environmental engineering. He has been researching methods for remote sensing approaches to civil infrastructure inspection for over two years as a Lafayette College EXCEL Scholar. His other research interests include concrete materials and study of local streamflow regime change. In addition to his research work, he is also heavily involved in Lafayette’s academic teams, including ASCE’s Steel Bridge and GeoWall competitions and ACI’s Concrete Beam competition. Upon graduation, he will begin his career working in the dam engineering group at Schnabel Engineering.