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28 FIGURE 31 Interactive visual simulation of the Okeechobee Road (U.S. Highway 27) project. The simulation used during the value engineering study CASE STUDY 7: VISUALIZATION FOR MACHINE changed perspectives quickly and efficiently to focus on CONTROL either a specific detail or a larger perspective. The aerial model prevented arguments by allowing users to zoom in on Contacts: the specific study area and have everyone looking at the same URS Creative Imaging Group thing at the same time. 700 Third Street South Minneapolis, MN 55415 The use of visualization was progressive, starting with Transportation Program Supervisor canned data from GIS information sources. As concepts were Minnesota DOT developed, standardized typical sections, aerial photography, Office of Technical Support and general project requirements were added to the visual- St. Paul, MN 55155-1899 ization. Visualization was an expandable and flexible tool for the value engineering team. Minnesota Department of Transportation ROC 52 Visualization Benefits to Value Engineering Process The reconstruction designbuild project on U.S. Highway 52 ("ROC 52"), located near Rochester, Minnesota, stretched The use of visualization during the value engineering process from Highway 63 to 85th Street NW. The project was needed fleshed out "what if" scenarios for the reviewers. The 3-D to reduce congestion, improve safety, replace deficient layers provided conflict identification points and phasing bridges and pavement, and eliminate the confusing mixed requirements for maintenance of traffic and construction frontage road system. It included six lanes from Highway 63 staging. to 75th Street NW; a new interchange at 75th Street NW; new and reconstructed local connecting frontage roads; new over- The varying degrees of abstraction were important from a passes at 65th Street NW and 85th Street NW; and recon- value analysis perspective because they provided different structed interchanges at 6th Street SW, 2nd Street SW, Civic levels of information, and the user could alter the constraints Center Drive, and 19th Street NW. of the project by turning on or off levels of information. This function could either aid or stifle the creative process by To enhance this large designbuild project and assist with focusing the user's attention on the "how" rather than the the machine control operations for the earthwork portion of "why." The overlay of the differing layers of information the project, visualization was used (see Figure 33). URS Cre- helped in the evaluation and analysis phases by comparing ative Imaging Group created 3-D DTMs of sections of the data in a graphical format that showed the combined effects project site. The AutoCAD-generated models were then of data (see Figure 32). loaded into a software program developed by Ziegler/CAT, and this software program linked the DTMs to geographic The shifting of value engineering to the earlier and perhaps positioning systems located on earthmoving equipment. more appropriate phases of the work program is a natural out- come of improved information and techniques that were made In 2002, Caterpillar and Trimble signed a joint venture more readily available though the use of visualization. agreement to develop and incorporate global positioning sys-

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29 FIGURE 32 Site plan overlay of different layers of information showing combined effects of data on Okeechobee Road simulation. tem technology into CAT machines. By using this technology, the survey stakes; in between stakes, it is guesswork, and earthwork operations were significantly improved; resulting in most operators will err on the high side to avoid undercut- faster construction schedules and reduced construction fees. ting, which is the most costly mistake. However, erring on the high side leads to an increased number of passes needed By relying on the DTMs, machine operators could view to get to final grade. Therefore, the use of DTMs for grading the grade control technology program on their machinery resulted in fewer grading passes, faster grading times, tighter while making their grading passes (see Figure 34). This abil- vertical and horizontal tolerances, reduced human error, and ity eliminated the need for expensive manual surveying, increased savings in schedules and budgets. URS Creative which is traditionally used. When operators use traditional Imaging Group calculated a 50% to 70% increase in field manual surveying, they only know when they are on-grade at performance as a result of DTMs. In this project, basic 3-D CADD design techniques were used to enhance the construction process. Visualization tech- nologies saved a significant amount of construction dollars FIGURE 33 Wire frame overlay showing visuals for ROC 52 (U.S. Highway 52) reconstruction designbuild project, near Rochester, Minnesota. (Courtesy : URS.) FIGURE 34 Digital terrain model. (Courtesy : URS.)

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30 and reduced the overall construction time on this heavily from the model. Because one of the products of the new soft- congested highway corridor. ware is a 3-D DTM of the top surface from tie-down to tie- down, 3-D modeling can also be used for visualization. Mn/DOT has numerous other groups besides design (e.g., Software for Machine Control hydraulics, construction, surveys, and landscape) that have use for the model. Another use for the 3-D model is to check To implement visualization for machine control in projects safety features (e.g., passing sight distances and how multi- throughout the department, Mn/DOT has been developing ple roadways interface with each other). A designer stated special software in conjunction with Bentley Systems. This that, "A tool like this would have pointed out the 94-Pascal software is considered part of the 3-D design process. problem of a few years ago in a matter of minutes, early in Although Mn/DOT is promoting the use of the software for the design process." machine control, the department is educating personnel to use the software during the design process as well. Mn/DOT is illustrating the potential of its new 3-D mod- eling software by showing the problems of designs done in the Rather than retrofitting modeling, which the DOT is cur- traditional "cross-section" method. Although the new soft- rently doing, the long-term goal is to do the 3-D modeling as ware is still a few years away from common use, Mn/DOT is part of the design workflow and then generate cross sections implementing it on a statewide basis starting in 2006.