For demonstration, two vertical sections of electrical resistivity data in Rice model Conclusion A major source of construction project risk relates to subsurface conditions. Yet geotechnical investigations are often limited to covering relatively small portions of project sites, resulting in extrapolation and interpretation being a necessity. In addition, this information is often presented in printed documents that limit communication necessary for reducing project risks. Holographic models, using a HoloLens and the Ada Platform, provide opportunities for data presentation and collaborative experiences to help project participants better understand risk and uncertainty associated with the underground environment and potential design options. A 3D holographic model allows stakeholders to see real data at its location in a scaled or full-sized project format. The Minnesota case study provides a holographic model that depicts values from multiple subsurface investigation techniques at the project setting, conveying the relationship of the geotechnical data to the in-situ environment and the proposed construction. The success of augmented reality in conveying greater understanding of the subsurface conditions of a Minnesota bridge site demonstrates how the 3D environment can serve as a useful tool to establish measurement locations and convey the scale, proportion and relationships of tested and untested materials in typical, robust site characterization programs. The 3D environment allows both geotechnical information and the associated risks of a project to be better visualized and comprehended, and therefore, to be better managed. The more efficient, tailored designs that can result add to project economy through better project definition, contractor prequalification (if appropriate), bid pricing and scheduling. While the example focused on transportation geotechnics, the 3D environment is wholly applicable for other structure types and in related engineering disciplines. In deploying a holographic model as part of the FHWA Every Day Counts (EDC) technology initiative, the authors have found that, despite being partly in the virtual world, the augmented reality shared experience is a “real” user experience. Scott Anderson, Ph.D., P.E., is a principal geotechnical engineer with BGC Engineering in Golden, Colorado. His career has focused on innovation and has spanned academia, research, consulting and many years with the FHWA. Ben Rivers, P.E., is a geotechnical engineer with the Federal Highway Adminis- tration Resource Center (FHWA-RC), where he manages site characterization and geophysical program efforts. He currently leads the EDC A-GaME initiative. Silas Nichols, P.E., is the principal geotechnical engineer for the Federal Highway Administration in Washington D.C. Nichols has been involved with several large implementation efforts for the FHWA, and has also worked in academia and consulting. Derrick Dasenbrock, P.E., D.GE, works for the Minnesota Department of Transportation as the geomechanics/LRFD engineer in the Office of Materials and Road Research. His responsibilities include development and implementation of new geotechnical practices to improve MnDOT’s geotechnical cost effectiveness and providing solutions for geotechnical construction and maintenance problems. 20 • DEEP FOUNDATIONS • MAY/JUNE 2020
