Design and Evaluation of a Single-Span Bridge Using Ultra- High Performance Concrete, September 2009

Research presented herein describes an application of a newly developed material called Ultra-High Performance Concrete (UHPC) to a single-span bridge. The two primary objectives of this research were to develop a shear design procedure for possible code adoption and to provide a performance evaluation to ensure the viability of the first UHPC bridge in the United States. Two other secondary objectives included defining of material properties and understanding of flexural behavior of a UHPC bridge girder. In order to obtain information in these areas, several tests were carried out including material testing, large-scale laboratory flexure testing, large-scale laboratory shear testing, large-scale laboratory flexure-shear testing, small-scale laboratory shear testing, and field testing of a UHPC bridge. Experimental and analytical results of the described tests are presented. Analytical models to understand the flexure and shear behavior of UHPC members were developed using iterative computer based procedures. Previous research is referenced explaining a simplified flexural design procedure and a simplified pure shear design procedure. This work describes a shear design procedure based on the Modified Compression Field Theory (MCFT) which can be used in the design of UHPC members. Conclusions are provided regarding the viability of the UHPC bridge and recommendations are made for future research.

Soft Photogrammetry for Highway Engineering, HR-387, 1998

The SoftPlotter, a soft photogrammetric software and Silicon Graphics workstation, was used to evaluate the accuracy of soft photogrammetry and identify applications of this technology to highway engineering. A comparative study showed that SoftPlotter compares well with other software such as Socket and Integraph. The PC software TNTMips is inexpensive but needs further development to be comparable to SoftPlotter. The Campus Project showed that soft photogrammetry is accurate for traditional photogrammetric applications. It is also accurate for producing orthophoto and base maps for Geographic Information Systems (GISs). The Highway Project showed that soft photogrammetry is accurate for highway engineering and that the technical staff at the Iowa Department of Transportation (IA DOT) can be easily trained in this new technology. The research demonstrated that soft photogrammetry can be used with low-flight helicopter photography for large-scale mapping in highway engineering. The researchers recommend that research be conducted to test the use of digital cameras instead of the traditional aerial cameras in helicopter photography. Research that examines the use of soft photogrammetry with video logging imagery for inventory and GIS studies in highway maintenance is also recommended. Research is also warranted into the integration of soft photogrammetry with virtual reality, which can be used in three-dimensional designing and visualization of highways and subdivisions in real time. The IA DOT owns one analytical plotter and two analogue plotters. The analytical plotter is used for aerial triangulation, and the analogue plotters are used for plotting. However, neither is capable of producing orthophotos. Therefore, the researchers recommend that the IA DOT purchase soft photogrammetric workstations for orthophoto production, and if and when required, use it for aerial triangulation and plotting. In the future, the analogue plotters may become obsolete. At that time, the researchers recommend that the analogue plotters be phased out and replaced by soft photogrammetric workstations.