Terrestrial laser scanner for geophysical hazard mitigation and infrastructure resiliency

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A terrestrial laser scanner (TLS) is requested to sustain and enhance civil engineering research in geophysical hazard mitigation and infrastructure resiliency. A TLS implements an automatically rotating laser range-finder to survey hundreds of thousands of points per second, from which a three dimensional (3D) point cloud is generated with high accuracy, leading to a 3D digital elevation model (DEM) of a natural and/or built environment. The proposed TLS will be used to develop several cutting-edge research projects. Studies of river morphodynamics will involve rapid scanning of exposed bar surfaces in the field and equilibrium bed bathymetry in mobile-bed laboratory flume experiments. Comparison of DEMs collected before and after flood events will permit evaluation of the morphodynamic and infrastructure impacts of flooding. The fundamental soil mechanics of volumetric deformation and movement of partially saturated soils due to varying environmental conditions will also be assessed with the TLS. This research has application to slope failures in river banks, dams breaching, and other geotechnical hazards. The TLS will also be used to map morphology of large river canyons for development of 3D flow and sediment transport models; canyon walls cannot be surveyed by any other means. Growth, consolidation, and decay of river ice covers will also be surveyed with the TLS. The resulting data will be used to validate newly developed algorithms for photogrammetric analysis of ice cover dynamics, including formation of ice jams linked to catastrophic flooding. River floods are not the only natural hazards that will be assessed with the TLS. Earthquake and tsunami post-disaster zones will be rapidly and safely surveyed using the TLS to evaluate the impacts on infrastructure due to these extreme loads, from which improved building codes can be developed. The survey of infrastructure will also be applied for generation of Building Information Models (BIMs) for view in a Virtual Reality Environment (VRE). This will include detailed analysis of crack development as surveyed using the TLS, enabling our research team to measure the status of existing structures (i.e., buildings; bridges), enabling decision-making regarding the level of maintenance, repair and replacement required to keep the infrastructure in acceptable operational conditions.