Sanghyeok Kang

GIS Method for Haul Road Layout Planning in Large Earthmoving Projects: Framework and Analysis

AbstractThis study presents a geographic information system (GIS)-based method for determining the optimal layout of a haul route for large earthmoving projects. The methodology focuses on the use of cost distance measurements to implement a least-cost path analysis to calculate the route with the shortest weighted distance between cut and fill areas. Various factors such as truck speed, construction costs, and land use that affect haul road layout are investigated. Linear interpolations based on linguistic evaluations of experienced field experts are utilized to quantify the factors. An earthmoving project from a large-scale dam construction was used as a case study to verify the applicability of the proposed method, and the route produced with the new method was compared to real road design data. The results showed the potential of the method as a practical approach to determining the optimal haul route for earthmoving.

Evaluation of Pedestrian Safety: Pedestrian Crash Hot Spots and Risk Factors for Injury Severity

Pedestrian-involved crashes that occurred in the city of San Francisco, California, over 6 years from 2002 to 2007 were analyzed to evaluate two key aspects of pedestrian safety: occurrence and severity. This analysis was done to identify locations with frequent occurrences of pedestrian-involved crashes and to examine various risk factors for the injury severity of pedestrian-involved crashes. A geographical information system analysis for hot spot identification showed that the frequency of pedestrian crashes was greater in the vicinity of the central business district but that the crash rate (the number of crashes per walking trip) was higher in the periphery of the city. For injury analysis, an ordered probit model was specified to evaluate risk factors that increased the probability of severe injury and fatality. Those factors were age (<15 and ≥65), alcohol consumption, and cell phone use among pedestrian characteristics; nighttime, weekends, and rainy weather among environmental characteristics; and, among crash characteristics, the influence of alcohol, larger vehicles (pickups, buses, and trucks), and vehicles proceeding straight and striking a pedestrian. The methods discussed are readily applicable to the evaluation of safety performance in other regions where pedestrian crash data are available.

Spatiotemporal Analysis of Macroscopic Patterns of Urbanization and Traffic Safety Case Study in Sacramento County, California

This study provides a preliminary investigation into the relationship between urbanization and traffic collisions by analyzing the spatial patterns in Sacramento County, California, from 1998 to 2008 through use of urban land classifications and traffic collision data. The ArcGIS directional distribution tool was used to create standard deviational ellipses to investigate the distributional trend of urban land and traffic collisions over time. Statistical outputs representing changes of geographical centroids, elliptical areas, and standard distances (long and short axes) were then compared. Collisions were also divided into subsets by severity level to account for inherent differences in the spatial distribution of different types of collisions. The results provided insight into the macroscopic spatial patterns of urban land and traffic safety and their relationships. The limitations of the method and the need for further research were discussed. The approach in this study would be useful for other metropolitan areas with similarly changing development patterns and can be helpful in guiding future research that compares these two phenomena.

GIS-Based Roadway Construction Planning

Roadway construction planning processes involve a large amount of information regarding design, construction methods, quantities, unit costs, and production rates. GIS (Geographic Information System) is a very effective tool for integrating and managing various types of information such as spatial and non-spatial data required for roadway construction planning. This paper proposes a GIS-based system for improving roadway construction planning by integrating design and construction information. The proposed system can also help construction planners make a proper decision in a unique way with its ‘Interactive Planning’ function that supports the space scheduling and activity sequence visualization processes.