Long C.,DKS Associates |
Buchanan K.,Signal Operations Technician
Institute of Transportation Engineers Annual Meeting and Exhibit 2010 | Year: 2010
The Seattle Central Link light rail began final design in 2000 and started revenue service in July 2009. When the project began, the City of Seattle and Sound Transit felt that the typical priority or preempt features available in the marketplace at the time would not satisfy the operational needs of the Martin Luther King Jr. Way S. corridor. Through the development of a VISSIM model of the Light Rail Transit (LRT) corridor and multiple needs evaluation sessions with the stakeholders, a new traffic signal controller software approach was born. The controller software started development in late 2005 and first hit the street for testing in the summer of 2008. The software includes multiple levels of priority and varying methods of recovery following an LRT priority event. Many of the features developed for this corridor have not been used on any other LRT system in the nation. The intent of the system was to have the least amount of impact on general purpose traffic and pedestrians; while progressing trains between stations without stopping. Despite all the flexibility and control developed in the system, in the end, the comments and concerns raised by the traveling public ultimately dictated how the corridor was operated. This paper will present the new and innovative forms of priority developed for this corridor and how they originated through the initial VISSIM analysis. This will be followed by a discussion of the publics' reaction to the system and the ultimate changes in operation that were accepted.
Loudon W.R.,DKS Associates |
Synn J.,FHWA |
Transportation Research Record | Year: 2010
Under FHWA sponsorship, DKS Associates conducted a national scan of how agencies in major metropolitan areas are developing plans for congestion pricing, managed lanes, or both. Staff members from the metropolitan planning organization (MPO) and the state department of transportation (DOT) in 10 metropolitan areas were surveyed to find out how they are including consideration of congestion pricing, managed lanes, or both in their metropolitan planning processes and the development of long-range transportation plans for the region. In addition, the study team identified projects already in operation in each region, those already in the long-range plan, and those being considered. The study results reported in this paper focused on how the MPOs, state DOTs, and other key agencies interact, contribute, and cooperate in considering congestion pricing or managed lanes. The study also produced information on methods used to evaluate these strategies, including modeling tools used, performance measures used, and how network effects, diversion of trips, and equity effects are taken into account. The study identified how federal grants were used to fund studies and projects in the early stages of consideration of congestion pricing or managed lanes in the 10 regions. Public and stakeholder involvement methods used by the MPOs and state DOTs to advance projects were also identified.
Chen A.,Utah State University |
Pravinvongvuth S.,DKS Associates |
Chootinan P.,Bureau of Planning
Transportmetrica | Year: 2010
Recently, a multi-objective model for locating the automatic vehicle identification (AVI) readers in a transportation network was proposed by the authors along with its solution procedure. The model locates the AVI readers by simultaneously considering three objectives: the equipment and installation cost (e.g. number of AVI readers), the coverage of the AVI system (e.g. number of origin-destination (O-D) pairs), and the amount/quality of travel information obtained (e.g. number of AVI readings). However, only a single travel demand pattern for a certain time period, such as the evening peak hour, was considered in determining the AVI reader locations. Therefore, the recommended AVI system may not be able to guarantee the amount of travel information gathered during other time periods. This study extends our previously proposed model by developing three scenario based models to accommodate different travel demand patterns observed during the whole day. A case study is provided to illustrate the applicability of the new models and the robustness of the AVI system designed by considering different travel demand patterns. © 2010 Hong Kong Society for Transportation Studies Limited.
Rowe D.,Chicago Bridge And Iron Company |
McCourt R.S.,DKS Associates |
Morse S.,Center for Neighborhood Technology |
Haas P.,Center for Neighborhood Technology |
Haas P.,Fermi National Accelerator Laboratory
ITE Journal (Institute of Transportation Engineers) | Year: 2013
Parking policies of the past five decades have focused extensively on the provision of parking in a uniform manner to avoid conflicts between land owners. Policies were directed to avoid undersupplying parking in order to ensure adequate parking for all uses. The intent was to reduce risks resulting from those who did not sufficiently invest in parking and who then encroached, poached, or spilled over onto other property owners' parking supply. Assuming that all new residential tenants must have parking wastes an excellent opportunity to match land use development with appropriate transportation services and travel patterns. In addition, this assumption increases the costs of housing in urban areas, which can have a large economic impact. One-size-fits-all parking policies are simple but, as the cities become more complex, they have resulted in onerous ordinances that do not take into account context-sensitive site characteristics and demographics.
Prinz G.S.,University of Arkansas |
Coy B.,DKS Associates |
Richards P.W.,Brigham Young University
Journal of Structural Engineering (United States) | Year: 2014
Buckling-restrained braced frame performance at high drifts is improved by providing beam splices that reduce demands in the gusset regions. Existing experimental data only consider web splices without a slab present. An alternative top-flange splice, proposed by others, was investigated experimentally and numerically. Two full-scale top-flange beam splices from a prototype frame were tested using the qualifying buckling-restrained brace frame cyclic loading protocol. During experimental testing, the gusset connection regions remained essentially undamaged through multiple cycles at 0.06 rad drift. The splice plates experienced low inelastic strains, but fatigue analyses indicate they could withstand over fourteen similar loading histories without requiring replacement. Finite-element models were used to investigate the influence of slabs on connections with web splices or top-flange splices. When slabs were considered, the top-flange splice transmitted over 70% less moment than the web splice. © 2014 American Society of Civil Engineers.