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Does Accessibility Require Density or Speed?

Levine, J., Grengs, J., Shen, Q., & Shen, Q. (2012). Does Accessibility Require Density or Speed?. Journal of the American Planning Association, 78(2), 157–172.

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Abstract

Problem, research strategy, and findings: Advocates of accessibility as a transportation performance metric often assert that it requires higher density. Conversely, traditional transportation planning methods have valued speed per se as an indicator of success in transportation. In examining these claims, we make two methodological innovations. The first is a new intermetropolitan gravity-based accessibility metric. Second, we decompose the impact of density on accessibility to highlight the distinct opposing influences of speed and proximity in a manner that illustrates different families of relationships between these two factors. This reveals that denser metropolitan regions have slower travel speeds but greater origin-destination proximity. The former effect tends to degrade accessibility while the latter tends to enhance it. Despite theoretical reasons to expect that the speed effect dominates, results suggest that the proximity effect dominates, rendering the denser metropolitan areas more accessible.

Takeaway for practice: Having destinations nearby, as when densities are high, offers benefits even when the associated congestion slows traffic. Where land use policy frequently seeks to support low-development densities in part in an attempt to maintain travel speeds and forestall traffic congestion, our findings suggest that compact development can often improve transportation outcomes.

Research support: Environmental Protection Agency project RD-83334901-0, FHWA Cooperative Agreement Number: DTFH61-07-H-00037, and the Graham Environmental Sustainability Institute at the University of Michigan.

Keywords

accessibility; mobility; speed; proximity; transportation planning

Transit-Oriented Development at the Urban Periphery: Insights from a Case Study in Shanghai, China

‌Pan, H., Shen, Q., & Liu, C. (2011).. Transit-Oriented Development at the Urban Periphery: Insights from a Case Study in Shanghai, China. Transportation Research Record: Journal of the Transportation Research Board, 2245(1), 95–102.

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Abstract

Major cities in China are extending rail transit into the urban periphery to counter urban growth and suburbanization that are automobile-driven and automobile-dependent. In the meantime, transit-oriented development (TOD) has been adopted widely in Chinese cities. Given the adoption of the TOD concept by many rail transit station areas at the peripheries of metropolitan regions, it is imperative to explore how TOD can be applied appropriately there. In this study, two station areas were examined in Songjiang, a district located approximately 30 km from the city center of Shanghai, China. These station areas have developed according to some basic TOD principles, and, in many important ways, they are representative of newly developed rail transit station areas in Shanghai and in other major Chinese cities. The conduct of a questionnaire survey allowed for investigation of resident travel behavior, assessment of the effectiveness of the TOD application, and discussion of how TOD should be adapted to peripheral locations in a large and complex metropolitan region. The study concluded that planners must carefully substantiate the basic TOD concept in connection with this particular kind of application setting. Careful consideration should be paid to mixed land use, differentiated density, and to pedestrian and bicycle travel and their connection with rail transit. Planners also must pay close attention to each peripheral area's economic and social conditions, as well as its relationships with the central city and with other parts of the metropolitan region. This case study not only provided timely feedback on current planning practice in Shanghai and other Chinese cities but also contributed to the literature on the adaptation of TOD to local circumstances.

 

Architecture for the Boston & Albany Railroad: 1881-1894

Ochsner, J. K. (1988). Architecture for the Boston & Albany Railroad: 1881-1894. Journal of the Society of Architectural Historians, 47(2), 109-131 .

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Abstract

Between 1881 and 1894 the Boston & Albany Railroad undertook a major program of capital investment and improvements to the physical facilities of the line, including the construction of over 30 new passenger stations. H. H. Richardson's close friends, James A. Rumrill and Charles S. Sargent, as the two members of the B&A Board most interested in construction, were given responsibility for this program. They directed the commissions to Richardson and after his death to his successors, Shepley, Rutan and Coolidge. Richardson's nine B&A station designs were generally variations on a simple theme-small rectangular stone blocks with overhanging roofs providing sheltered waiting space at trackside. The continuation of this approach by Shepley, Rutan and Coolidge in 23 additional station designs resulted in a remarkable consistency of character and quality throughout the B&A system. This consistency was also fostered by the continuing participation of Norcross Brothers of Worcester (Richardson's "Master Builder") as contractor, and by the participation of F. L. Olmsted, whose design of landscaped settings for many of the stations contributed to the establishment of the B&A program of "railroad gardening." While the stations were small commissions, the totality of the B&A program represents an impressive collaboration of designer, contractor, and client which has seldom been equalled.

Using Open Data and Open-source Software to Develop Spatial Indicators of Urban Design and Transport Features for Achieving Healthy and Sustainable Cities

Boeing, Geoff; Higgs, Carl; Liu, Shiqin; Giles-corti, Billie; Sallis, James F.; Cerin, Ester; Lowe, Melanie; Adlakha, Deepti; Hinckson, Erica; Moudon, Anne Vernez; Salvo, Deborah; Adams, Marc A.; Barrozo, Ligia, V; Bozovic, Tamara; Delclos-alio, Xavier; Dygryn, Jan; Ferguson, Sara; Gebel, Klaus; Thanh Phuong Ho; Lai, Poh-chin; Martori, Joan C.; Nitvimol, Kornsupha; Queralt, Ana; Roberts, Jennifer D.; Sambo, Garba H.; Schipperijn, Jasper; Vale, David; Van De Weghe, Nico; Vich, Guillem; Arundel, Jonathan. (2022). Using Open Data and Open-source Software to Develop Spatial Indicators of Urban Design and Transport Features for Achieving Healthy and Sustainable Cities. Lancet Global Health, 10(6), E907-E918.

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Abstract

Benchmarking and monitoring of urban design and transport features is crucial to achieving local and international health and sustainability goals. However, most urban indicator frameworks use coarse spatial scales that either only allow between-city comparisons, or require expensive, technical, local spatial analyses for within-city comparisons. This study developed a reusable, open-source urban indicator computational framework using open data to enable consistent local and global comparative analyses. We show this framework by calculating spatial indicators-for 25 diverse cities in 19 countries-of urban design and transport features that support health and sustainability. We link these indicators to cities' policy contexts, and identify populations living above and below critical thresholds for physical activity through walking. Efforts to broaden participation in crowdsourcing data and to calculate globally consistent indicators are essential for planning evidence-informed urban interventions, monitoring policy effects, and learning lessons from peer cities to achieve health, equity, and sustainability goals.

Keywords

Systems; Access; Care

Qing Shen awarded funding for commute research survey

The Mobility Innovation Center announced that Qing Shen, professor of Urban Design & Planning and an expert in transportation planning and policy, has received a $100,000 award to study commuting patterns and develop a model to understand the effect of telework and flexible scheduling. The project will build off the existing Commute Trip Reduction (CTR) survey for employers who are in the CTR program as required by state law in the central city portion of Seattle. In addition, a complementary…

Assessment of Data Quality for Evaluations of Manual Pavement Distress

Bogus, Susan M.; Migliaccio, Giovanni C.; Cordova, Arturo A. (2010). Assessment of Data Quality for Evaluations of Manual Pavement Distress. Transportation Research Record, 2170, 1 – 8.

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Abstract

Assessment of the conditions of current assets is a task of major relevance in a transportation agency asset management program It not only provides information on the current condition of the asset but also helps the agency make decisions on future maintenance and rehabilitation activities Although low volume roadways represent a large proportion of the total road network in the United States little research on the management of these assets has been done Two major data collection techniques are used for roadway condition assessment manual and automated Although automated techniques have been found to be safer and quicker manual condition surveys have been proven to offer preciseness and cost effectiveness In the case of low volume roadway assessment for which the funds available to asset managers are limited manual condition surveys are often preferred Nevertheless manual condition surveys must address the potential subjectivity of the results Therefore agencies could benefit from a system for ensuring quality on manual condition surveys This paper proposes a framework for assessment of data quality and presents a case study of its implementation in the Northern New Mexico Pavement Evaluation Program The proposed framework is easily implementable and able to identify potential and actual data collection issues The framework can be used as part of an asset management program and could be particularly beneficial in the case of low volume roads

Keywords

Interrater Reliability; Agreement; Ratings

When To Partner For Public Infrastructure?

Whittington, Jan. (2012). When to Partner for Public Infrastructure? Journal Of The American Planning Association, 78(3), 269 – 285.

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Abstract

Problem, research strategy, and findings: Public agencies traditionally request bids and award contracts to private firms after infrastructure designs are complete (bid-build). They also increasingly partner with private firms, often by folding capital improvements into a contract to design and build (design-build). The latter involves much more than the mere transfer of design work to the private sector, such as time to completion; the merits or problems of design-build strategies can, thus, be difficult to isolate. This article presents a method for doing so. Together with the development of a theory of contracting, the comparative analysis of two very similar highway overpass projects, one design-build and the other bid-build, demonstrates how so-called transaction cost economics can clarify the details of partnership cost-effectiveness. Takeaway for practice: Transaction cost analysis disaggregates and evaluates the costs of completed projects, accounting for factors typically external to economic analysis. My approach reveals tradeoffs between variables of interest to planners, such as the pace of delivery, public participation, environmental compliance, and the transfer of risk of cost overrun to the private sector.

Keywords

Design & Build Contracts; Bridges; Infrastructure (economics); Transaction Costs; Construction Contracts; Public-private Sector Cooperation; Transportation Planning; Design-build; Evaluation; Infrastructure; Public–private Partnership; Transaction Cost; Vertical Integration; Contracting Process; Privatization; Firm; Services; Reverse; Lie; Public-private Partnership

Relation between Higher Physical Activity and Public Transit Use

Saelens, Brian E.; Moudon, Anne Vernez; Kang, Bumjoon; Hurvitz, Philip M.; Zhou, Chuan. (2014). Relation between Higher Physical Activity and Public Transit Use. American Journal Of Public Health, 104(5), 854 – 859.

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Abstract

Objectives. We isolated physical activity attributable to transit use to examine issues of substitution between types of physical activity and potential confounding of transit-related walking with other walking. Methods. Physical activity and transit use data were collected in 2008 to 2009 from 693 Travel Assessment and Community study participants from King County, Washington, equipped with an accelerometer, a portable Global Positioning System, and a 7-day travel log. Physical activity was classified into transit-and non-transit-related walking and nonwalking time. Analyses compared physical activity by type between transit users and nonusers, between less and more frequent transit users, and between transit and nontransit days for transit users. Results. Transit users had more daily overall physical activity and more total walking than did nontransit users but did not differ on either non-transit-related walking or nonwalking physical activity. Most frequent transit users had more walking time than least frequent transit users. Higher physical activity levels for transit users were observed only on transit days, with 14.6 minutes (12.4 minutes when adjusted for demographics) of daily physical activity directly linked with transit use. Conclusions. Because transit use was directly related to higher physical activity, future research should examine whether substantive increases in transit access and use lead to more physical activity and related health improvements.

Keywords

Transportation; Analysis Of Covariance; Analysis Of Variance; Chi-squared Test; Comparative Studies; Confidence Intervals; Geographic Information Systems; Research Funding; Statistics; Walking; Data Analysis; Accelerometry; Cross-sectional Method; Exercise Intensity; Physical Activity; Diary (literary Form); Descriptive Statistics; Washington (state); Work; Car; Impact

Innovative Linear Formulation for Transportation Reconstruction Planning

El-Anwar, Omar; Ye, Jin; Orabi, Wallied. (2016). Innovative Linear Formulation for Transportation Reconstruction Planning. Journal Of Computing In Civil Engineering, 30(3).

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Abstract

Following disasters, the pace of restoring transportation networks can have a significant impact on economic and societal recovery. However, reconstruction and repair efforts are typically faced by budget constraints that require careful selection among competing contractors. This paper presents an innovative formulation to optimize this complex planning problem in order to maximize the rate of transportation network recovery while minimizing the associated reconstruction costs. This study first contributes to the body of knowledge by offering an effective and efficient means of identifying the optimal schedules for reconstruction projects and the optimal contractor assignments. This is achieved by solving the problem using a new mixed-integer linear programming model. However, there are four main formulation challenges to represent this problem using linear equations because of the need to use logical operators. As such, the second contribution of this study is in offering innovative solutions to overcome these formulation challenges, which are generalizable to other construction scheduling and planning problems. This paper is companion to another paper that describes a holistic optimization and traffic assessment methodology for post-disaster reconstruction planning for damaged transportation networks. (C) 2015 American Society of Civil Engineers.

Keywords

Integer Programming; Linear Programming; Transportation; Innovative Linear Formulation; Transportation Reconstruction Planning; Economic Recovery; Societal Recovery; Complex Planning Problem; Transportation Network Recovery; Mixed-integer Linear Programming Model; Traffic Assessment Methodology; Postdisaster Reconstruction Planning; Natural Disasters; Housing Projects; Construction; Optimization; Performance; Robustness; Earthquake; Efficiency; Recovery; Plans; Transportation Network Reconstruction; Post-disaster Recovery; Multi-objective Optimization; Mixed-integer Linear Programming; Contractors Assignment; Linear Formulation; Reconstruction Costs