2013 Session: 679

• Comprehensive Three-Dimensional Methodology for Design, Assessment, and Checking Process of Rural Roads
  Abstract: The planning and approval process for rural roads takes place in Germany iteratively within various design stag-es, each with a subsequent approval process. This gives rise to planning and approval times of approx. 15 - 20 years before a rural road is completed. A new kind of multi-stage methodology is currently being developed as part of a research project for the design, assessment and testing process for rural roads. Following the three-dimensional design in real time (stage 1) with an iterative 3D model at a special design workstation, a new kind of procedure with a sectoral power wall, a multi-functional box and special interactive tools are available for the assessment process in stage 2. As a result, it is possible to illustrate the assessment and decision processes in a better way and make everything clearer. After optimizing the route as a result of the assessment process, the subsequent stage 3 provides a quality check to integrate the route in its surroundings with the help of augmented reality tools – i.e. reality is cross-faded with virtual graphics. A real motion path can be selected or individual positions for the virtual cross-fading process. The theoretical principles for the individual stages in the compre-hensive methodology and the crucial hardware and software tools are available as prototypes for initial practical tests. The results obtained will flow directly into the optimization and validation of the comprehensive methodology.
  Authors: Kuehn, Wolfgang; Kubik, Ronny; Leithoff, Ingolf
  Authors: Kuehn, Wolfgang; Kubik, Ronny; Leithoff, Ingolf
  Year: 2013
  Document Type: Paper
  Subject: Design
  Session: 679
  Paper Number: 13-1990
• Using Microsimulation to Support Decisions on Transport Infrastructure Planning: Case Study
  Abstract: Through a case study, this paper demonstrates the approach of using micro simulation tools in supporting urban infrastructure planning decisions. The study shows that the approach has great advantages over the current decision making support mechanism: it has large flexibility, it is technically sound, it can be done very quickly, and its powerful visualization capability can significantly reduce the communication gap between technical people and decision makers. While it lacks field observations during infrastructures¡¯ planning stage, micro simulation is usually able to pick up the performance differences for various alternative plans by using some default or assumed parameters and input data based on engineering judgment or practice manual assumptions. In the case study, using the simulation result, the authorities were quickly convinced to adopt a better alternative. It turned out that the approach is quite effective and worth some attention.
  Authors: Wang, Zhigao; Tang, Chong; Shen, Feng
  Authors: Wang, Zhigao; Tang, Chong; Shen, Feng
  Year: 2013
  Document Type: Paper
  Subject: Design
  Session: 679
  Paper Number: 13-3672
• Decision Tool to Define and Quantify Interchange Complexity
  Abstract: Because complexity is typically a qualitative characteristic, the ability to objectively evaluate the complexity of an interchange is somewhat difficult. This difficulty is compounded when trying to compare the complex features of multiple interchanges. This paper discusses a spreadsheet-based decision tool developed as a method of quantifying and comparing the complexity of freeway interchanges in the United States. Initial discussion focuses on the steps that guided researchers in developing the spreadsheet, followed by a description of the spreadsheet itself and how practitioners can use it to evaluate the complexity of interchanges under their consideration. The paper also contains a review of the results researchers obtained from the spreadsheet in an evaluation of the complexity of 28 existing interchanges in 11 states; these study sites ranged from relatively simple to very complex, and results indicate that the spreadsheet generated scores that were generally consistent with researchers’ qualitative estimation of the sites’ relative complexity. The concluding section of the paper contains discussion on what the spreadsheet results mean and how they can be interpreted.
  Authors: Brewer, Marcus A.; Fitzpatrick, Kay; Chrysler, Susan T.
  Authors: Brewer, Marcus A.; Fitzpatrick, Kay; Chrysler, Susan T.
  Year: 2013
  Document Type: Paper
  Subject: Design
  Session: 679
  Paper Number: 13-5219
• Safety Impacts of Design Exceptions on Nonfreeway Segments
  Abstract: The objective of this research was to compare safety, measured by expected crash frequency and severity, on road segments where design exceptions were approved and constructed to similar road segments where no design exceptions were approved or constructed. Data were collected for design exceptions in Utah in the years 2001 through 2006. Multiple data sources were used to identify and define road segments with and without design exceptions. Propensity scores were applied in this study to assess similarities between treatment and comparison sites. Ultimately, a total of 34 non-freeway segments with design exceptions and 80 non-freeway segments without design exceptions were used for modeling. The relationship between design exception presence and crash frequency was explored using a negative binomial regression modeling approach. The relationship between design exception presence and crash severity was explored in three ways: 1) computing severity distributions at locations with and without design exceptions; 2) estimating separate negative binomial regression models by severity level; and 3) estimating multinomial logit models to predict the severity outcome of a crash. Design exception presence was represented in the regression models by an indicator variable (1 = one or more design exceptions; 0 = no design exceptions). Crash data from the years 2007 through 2010 were used for model estimation. There were no significant differences in expected crash frequencies and crash severities between non-freeway road segments with and without design exceptions. This overall finding is consistent with two previous, related efforts in Kentucky and Indiana.
  Authors: Wood, Jonathan S.; Porter, Richard Jon
  Authors: Wood, Jonathan S.; Porter, Richard Jon
  Year: 2013
  Document Type: Paper
  Subject: Design
  Session: 679
  Paper Number: 13-4078
  Practice-Ready: Yes
• Comprehensive Three-Dimensional Methodology for Design, Assessment, and Checking Process of Rural Roads
  Authors: Kuehn, Wolfgang
  Authors: Kuehn, Wolfgang
  Year: 2013
  Document Type: Presentation
  Subject: Design
  Session: 679
  Paper Number: 13-1990
• Using Microsimulation to Support Decisions on Transport Infrastructure Planning: Case Study
  Authors: Wang, Zhigao
  Authors: Wang, Zhigao
  Year: 2013
  Document Type: Presentation
  Subject: Design
  Session: 679
  Paper Number: 13-3672
• Safety Impacts of Design Exceptions on Nonfreeway Segments
  Authors: Porter, Richard
  Authors: Porter, Richard
  Year: 2013
  Document Type: Presentation
  Subject: Design
  Session: 679
  Paper Number: 13-4078
• Decision Tool to Define and Quantify Interchange Complexity
  Authors: Brewer, Marcus
  Authors: Brewer, Marcus
  Year: 2013
  Document Type: Presentation
  Subject: Design
  Session: 679
  Paper Number: 13-5219