Title

“Explaining Gender Difference in Bicycling Behavior”;“Factors Associated with Proportions and Miles of Bicycle Rides for Transportation and Recreation in 6 Small US Cities”;"Micromechanical Investigation of Foamed Asphalt Mix Behavior: on the Curing Mechanism and the Effects of Mixing Moisture Content";"Pareto-Improving Ramp Metering Strategies for Reducing Congestion in the Morning Commute";"Carsharing and the Built Environment: A GIS-based Study of One U.S. Operator";"The Impact of Product Type and Other Variables on Store and Internet Purchase Intentions: Clothing versus Books"

Abstract

“Explaining Gender Differences in Bicycling Behavior”



Although men and women bicycle at relatively equal rates in industrialized countries such as the Netherlands, Germany, and Denmark, research has consistently found that in the United States men’s total bicycle trips surpass women’s by a ratio of at least 2:1. Current evidence, although limited, suggests that women are affected to greater or lesser degrees than men by some factors. The purpose of this study is to provide insight on how gender influences the decision to use a bicycle, with the intent of supporting policy development aimed at increasing bicycle ridership, particularly among women. Bicycle use in six small cities in the western U.S. is examined in an effort to determine how gender interacts with individual factors and social and physical environments to influence bicycle behavior. Analysis of data from an on-line survey using a binary logistic regression approach shows strong interaction of gender with certain individual factors, especially safety perception and household responsibilities, and to a lesser degree with social and environmental factors to influence bicycle behavior.



“Factors Associated with Proportions and Miles of Bicycle Rides for Transportation and Recreation in 6 Small US CIties”



The level of utilitarian bicycling is low in the United States compared to some European countries with similar living standards and auto ownership. Differences in the physical and social environments in these countries may explain this phenomenon. Previous research has established a potential association between environmental factors and transportation-oriented bicycling. However, empirical knowledge about the influence of physical-environment and social-environment factors on bicycle rides for transportation and recreation is limited. This study uses data from an online survey conducted in 2006 in six small cities in the western United States. For the subsample of respondents who bicycled within the last year, a binary logit proportion model reveals variables related to the proportion of bicycling for transportation compared with that for recreation. Factors associated with miles of bicycling for transportation and recreational purposes are identified using linear regressions. The results show residential preference for bicycling has positive influences on both the proportion and miles of transportation bicycling. Physical-environment factors influence transportation bicycling as well as recreational bicycling. Longer distances to destinations are negatively associated with the proportion and miles of bicycle rides for transportation but contribute to miles of recreational bicycling. Transit access correlates positively with the proportion of bicycling for transportation. Perceived bicycling safety is associated with bicycling miles for both purposes. Social-environment factors influence proportions and miles of bicycling for both purposes, after accounting for individual factors and physical-environment factors.



“Micromechanical Investigation of Foamed Asphalt Mix Behavior: on the Curing Mechanism and the Effects of Mixing Moisture Content”



Full depth reclamation (FDR) of flexible pavement with foamed asphalt stabilization is a promising pavement rehabilitation technique. This technique offers a rapid construction process, with minimal disruption to traffic. More importantly, it reuses and stabilizes aggregates in existing pavements, thereby minimizing the environmental impacts associated with extraction and transport of new aggregates. Despite of all the benefits, its implementation has been relatively slow since its debut in California in 2001, mainly due to the lack of fundamental understanding of foamed asphalt treated material’s behavior. The University of California Pavement Research Center conducted a four-year comprehensive study sponsored by Caltrans from 2004 to 2008. Presented in these two posters are two sub-tasks of this study. One investigated the curing mechanism of foamed asphalt, and the other one studied how mixing moisture content affect asphalt dispersion in the mix, and in turn its effects on mix properties. In addition to conventional laboratory testing, both studies employed innovative micromechanical approaches, which have provided clear and strong visual evidence to support the conclusions.



These two studies will be presented at the 2009 Annual Meeting of TRB, session #543. The following two relevant papers have been submitted to journals for publication consideration:


1.Fu, P., Jones, D., Harvey, J.T., and Halles F.A. (2008). “Curing Mechanism of Foamed Asphalt Mixes Based on Micromechanics Principles.” Journal of Materials in Civil Engineering, ASCE, submitted.


2.Fu, P., Jones, D., and Harvey, J.T. (2008). “Micromechanics of the Effects of Mixing Moisture on Foamed Asphalt Mix Properties.” Construction and Building Materials, submitted.


“The Impact of Product Type and Other Variables on Store and Internet Purchase Intentions: Clothing versus Books”


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