Xiaoguang Wang, Email: wang9x@cmich.edu Assistant Professor, Department of Geography, Central Michigan University Chao Liu, Email: cliu8@umd.edu Research Associate, National Center for Smart Growth, Research and Education, University of Maryland Lidia Kostyniuk, Email: lidakost@umich.edu Research Scientist, University of Michigan Transportation Research Institute Qing Shen, Email: qs@u.washington.edu Professor and Chair, Department of Urban Design and Planning College of Built Environments, University of Washington Shan Bao, Email: shanbao@umich.edu Research Fellow, University of Michigan Transportation Research Institute
Complete Street Sprawl Street Birmingham, MI Whittaker Rd, MI
Whether and to what extent does the street environment influence fuel efficiency? More specifically Whether and to what extent do complete streets decrease fuel efficiency, and whether there might be countermeasures to improve fuel efficiency of such complete streets?
Roadway Environment On road (lanes, lane widths, pavements, intersections, speed limit,traffic lights, etc.) Off road (business patterns, land uses, parking, density) Trip Trip purpose Trip length Time of day Drivers Gender Age Weather Temperature Rain/Snow Traffic condition Volume (congestion or not) Driving behavior Speed acceleration/decelera tion Energy consumption rate Vehicle Technology Age Size
GPS Traces Integrated Vehicle-Based Safety Systems (IVBSS) collected by University Michigan Transportation Research Institute (UMTRI), 2009-2010 108 automobile drivers driving 2006-07 Honda Accord LX sedans over 40 days with a data collection frequency of 10 Hz (26 GB data) Will be used to derive fuel rate, trip characteristics, driver characteristics, traffic condition, weather, and driving behaviours Road environments Road network data provided by Southeast Michigan Council of Governments (SEMCOG), 2011 Business pattern data from InfoUSA, 2006 Population data from Census 2010
Fuel efficiency for the m th trip travelling on the n th segment* * Segments which have been travelled by at least 5 different drivers were selected Road segment 1 Road segment 2 Road segment 3 Driver 2 Trip 3 Driver 2 Trip 2 Driver 2 Trip 1 Driver 1 Trip 2 Driver 1 Trip 1
Road segment 1 Road segment 2 Road segment 3 Off road environment (buffer area) Big box density Small retail density Population density Employment density On road environment Speed limit # of lanes Intersection density
Roadway Environment On road (lanes, lane widths, pavements, intersections, speed limit, stop signs,traffic lights, etc.) Off road (business patterns, land uses, parking, density) Trip Trip purpose* Trip length Time of day Drivers Gender Age Weather Temperature Rain/Snow Traffic condition Volume (congestion or not) Driving behavior Speed acceleration/decelera tion Energy consumption rate Vehicle (controlled) Technology Age Size
108 drivers 16,886 trips 4,711 road segments 197,652 trip segments Average fuel economy: 25.59 miles per gallon
Mean Std. Minimu Deviation m Maximum Women 0.42 0.49 0.00 1.00 Young 0.35 0.48 0.00 1.00 Middle 0.37 0.48 0.00 1.00 Old 0.28 0.45 0.00 1.00 Highway 0.52 0.50 0.00 1.00 City 0.48 0.50 0.00 1.00 Speed Limit 52.77 15.37 0.00 70.00 # of Lanes 3.33 1.29 0.00 8.00 Intersection density at 0.1 mile 2.71 2.88 0.00 32.59 Employment density at 0.1 mile 984.84 4,439.23 0.00 213,502.40 Population density at 0.1 mile 589.62 1,117.70 0.00 14,743.71 Big box density at 0.1 mile 0.16 0.46 0.00 7.57 Small retail density at 0.1 mile 4.67 8.64 0.00 123.61 Intersection density at 0.25 mile 4.99 5.87 0.00 98.15 Employment density at 0.25 mile 1,254.84 4,600.43 0.00 115,677.44 Population density at 0.25 mile 1,296.83 1,493.15 0.00 14,631.89 Big box density at 0.25 mile 0.43 0.84 0.00 8.70 Small retail density at 0.25 mile 11.39 18.76 0.00 190.72
Young Middle Old Total Young Middle Old Total Young Middle Old Total Middle age women has the highest average fuel economy; older women has the lowest. Young drivers have lower fuel economy. 27.5 27.0 26.5 26.0 25.5 25.0 24.5 24.0 23.5 23.0 Mean Fuel Economy (mpg) Male Female Total *Drivers are equally divided by gender and age groups
Fuel Economy (mpg) 35 30 25 20 15 10 5 0 interstate other freeways other principal arterial minor arterials major collectors 40% 35% 30% 25% 20% 15% 10% 5% 0% % of trip segments Fueleconomy.gov
Coefficients Sig. (Constant) 17.9071 0.00 Speed limit 0.0996 0.00 # of Lanes 0.0716 0.00 Intersection Density 0.0449 0.00 Employment Density -0.0001 0.00 Population Density 0.0001 0.00 Big box density -0.4325 0.00 Small retail density -0.0363 0.00 Women 0.1618 0.00 Young -1.0068 0.00 Old -0.1016 0.05 Highway 5.4387 0.00 Higher speed limit, higher number of lanes, higher intersection density -> higher fuel economy Both big box and small retails decrease fuel economy Women has better fuel economy
refine sprawl and complete streets typology testing structural equation models Use traffic and driving behaviors (speed, acceleration, cruising, etc.) as intermediate variables Refine road segment selections
A U shape
Coefficients Sig. (Constant) 23.2822 0.00 Speed Limit 0.0968 0.00 # of Lanes 0.1208 0.00 Intersection Density 0.0426 0.00 Employment Density 0.0000 0.00 Population Density -0.0001 0.00 Big box density -0.5233 0.00 Small retail density -0.0864 0.00 Women 0.2076 0.00 Young -0.9745 0.00 Old -0.0369 0.47 City Roads -5.2980 0.00 Higher speed limit, higher number of lanes, higher intersection density -> higher fuel economy Both big box and small retails decrease fuel economy Women has better fuel economy