2013 Session: 251

• Effect of Weather and Road Surface Conditions on Traffic Speed of Rural Highways
  Abstract: This paper describes a study focusing on the impact of winter weather and road surface conditions on the average vehicle speed of rural highways with the intention of examining the feasibility of using traffic speed from traffic sensors as an indicator of the performance of winter road maintenance (WRM). Detailed data on weather, road surface conditions, and traffic over three winter seasons from two two-lane and two four-lane rural highways in Iowa, US, are used for this investigation. Three modeling techniques are applied and compared for modeling the relationship between traffic speed and various road weather and surface condition factors, including multivariate linear regression, artificial neural network (ANN), and time series analysis. The modeling results have confirmed the statistically strong relationship between traffic speed and road surface conditions, suggesting that speed could potentially be used as an indicator of bare pavement conditions and thus the performance of winter road maintenance operations. The analysis has also confirmed the expected effects of several weather variables including precipitation, visibility, temperature and wind speed. Lastly, the time series model developed could be a valuable tool for predicting real-time traffic conditions based weather forecast and planned maintenance operations.
  Authors: Cao, Luchao; Thakali, Lalita; Fu, Liping; Donaher, Garrett
  Authors: Cao, Luchao; Thakali, Lalita; Fu, Liping; Donaher, Garrett
  Year: 2013
  Document Type: Paper
  Subject: Maintenance and Preservation; Safety and Human Factors
  Session: 251
  Paper Number: 13-0779
  Practice-Ready: Yes
• Approach to Optimization of Winter Road Management Operation by Taxi Probe Data
  Abstract: Traffic smoothness must be ensured through winter road management. The average travel speed is a key of indicator that represents traffic smoothness. In this study, we used taxi probe data to obtain average travel speeds in the Sapporo urban area, Japan for a long period of time, and analyzed the relationship between the average travel speed and various winter weather and road surface conditions. Also, we calculated the monetary value of the increase in average travel speed afforded by snow and ice control operations. We had been acquired taxi probe data 6 months from October 1st, 2010 to March 31st, 2011, with the cooperation of a taxi company. Differences in average travel speed between the winter season and the non-winter season have been found to vary depending on weather and road surface conditions. Our survey has found that snow and ice control operations increase the average travel speed of road users. Improved average travel speed increases the benefits for road users. The cost-benefit analysis of snow and ice control operations for national highways in Sapporo found that the estimated benefits of winter road management operations far exceeded the cost of such work operations. This paper proposes an approach to a balance and optimization of winter road management and winter service using the taxi probe data.
  Authors: Munehiro, Kazunori; Kageyama, Hiroyuki; Takahashi, Naoto; Ishida, Tateki; Asano, Motoki
  Authors: Munehiro, Kazunori; Kageyama, Hiroyuki; Takahashi, Naoto; Ishida, Tateki; Asano, Motoki
  Year: 2013
  Document Type: Paper
  Subject: Maintenance and Preservation; Safety and Human Factors
  Session: 251
  Paper Number: 13-0952
  Practice-Ready: Yes
• Remote Sensing of Weather and Road Surface Conditions: Is Technology Mature for Reliable ITS Applications?
  Abstract: Advances in road weather sensing technologies have made non-invasive road weather sensors a valuable component in many Intelligent Transportation Systems (ITS) applications. The current study presents an investigation into the reliability of using one of the aforementioned sensors for a proposed weather-responsive variable speed limit system. The Vaisala surface state and temperature sensors (DSC-111 and DST-111) were selected for the proposed application. The sensors’ ability to provide accurate and reliable data was tested under various conditions in a controlled laboratory environment. Specifically, four outputs of interest from the sensors were tested in this investigation; surface state, snow and ice depth, water depth and grip level. Testing results showed that the sensors determined the surface state (dry, moist, wet, snowy and icy) accurately and reliably. The sensor’s snow depth readings were found to be inaccurate, while the sensor’s ice depth measurements were found to be relatively close to the actual depths. In regards to water depth, only a limited number of readings were close to the actual depths while other readings were highly inaccurate. In an effort to test the potential of the sensor in providing reliable inputs to the proposed ITS application, a calibration was conducted for the sensor water depth measurements using various water depths and sensor installation angles. Calibration results showed that the water depth could be accurately estimated using the calibrated sensor measurements regardless of water depth or sensor installation angle. Sensor estimates of grip level were found highly correlated to the coefficient of static friction for the conditions considered in this study. Keywords: weather sensor, snow, friction, calibration, ITS
  Authors: Ewan, Levi; Al-Kaisy, Ahmed; Veneziano, David A.
  Authors: Ewan, Levi; Al-Kaisy, Ahmed; Veneziano, David A.
  Year: 2013
  Document Type: Paper
  Subject: Maintenance and Preservation; Safety and Human Factors
  Session: 251
  Paper Number: 13-1997
  Practice-Ready: Yes
• Estimating Statewide Benefits of Winter Maintenance Operations
  Abstract: Winter highway maintenance activities offer direct and indirect benefits to the public. However, the cost of such activities is such a major outlay that it demands close scrutiny. There is a need to better understand and quantitatively estimate the benefits of winter road maintenance. Therefore, the work discussed in this paper was undertaken to quantitatively assess the benefits of winter highway operations at the state level. Methodologies were developed for estimating the major benefits of winter maintenance, including safety improvements, travel time savings and fuel savings. A Minnesota case was used to demonstrate the methodologies and quantify those benefits. Results of the case study showed that the benefits of winter highway maintenance by the Minnesota Department of Transportation to be $227 million per winter season, with $168 million of safety benefits, $11 million of mobility benefits, and $48 million of fuel savings. The benefit-cost ratio of winter highway operations in Minnesota was 6.2, in which material costs were taken into account.
  Authors: Ye, Zhirui; Veneziano, David A.; Shi, Xianming
  Authors: Ye, Zhirui; Veneziano, David A.; Shi, Xianming
  Year: 2013
  Document Type: Paper
  Subject: Maintenance and Preservation; Safety and Human Factors
  Session: 251
  Paper Number: 13-2148
  Practice-Ready: Yes
• Effect of Weather and Road Surface Conditions on Traffic Speed of Rural Highways
  Authors: Cao, Luchao
  Authors: Cao, Luchao
  Year: 2013
  Document Type: Presentation
  Subject: Maintenance and Preservation; Safety and Human Factors
  Session: 251
  Paper Number: 13-0779
• Approach to Optimization of Winter Road Management Operation by Taxi Probe Data
  Authors: Munehiro, Kazunori
  Authors: Munehiro, Kazunori
  Year: 2013
  Document Type: Presentation
  Subject: Maintenance and Preservation; Safety and Human Factors
  Session: 251
  Paper Number: 13-0952
• Estimating Statewide Benefits of Winter Maintenance Operations
  Authors: Shi, Xianming
  Authors: Shi, Xianming
  Year: 2013
  Document Type: Presentation
  Subject: Maintenance and Preservation; Safety and Human Factors
  Session: 251
  Paper Number: 13-2148
• Estimating Statewide Benefits of Winter Maintenance Operations
  Authors: Veneziano, David
  Authors: Veneziano, David
  Year: 2013
  Document Type: Presentation
  Subject: Maintenance and Preservation; Safety and Human Factors
  Session: 251
  Paper Number: 13-2148
• Remote Sensing of Weather and Road Surface Conditions: Is Technology Mature for Reliable ITS Applications?
  Authors: Ewan, Levi
  Authors: Ewan, Levi
  Year: 2013
  Document Type: Presentation
  Subject: Maintenance and Preservation; Safety and Human Factors
  Session: 251
  Paper Number: 13-1997