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Launching Bus Rapid Transit (BRT) with Only One Dedicated Lane for Two-Way Bus Traffic on Congested Corridors. H.-S. Jacob Tsao , Wenbin Wei and Agus Pratama College of Engineering, San Jose State University, San Jose, California, USA Jason R. Tsao
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Launching Bus Rapid Transit (BRT) with Only One Dedicated Lane for Two-Way Bus Traffic on Congested Corridors H.-S. Jacob Tsao, Wenbin Wei and AgusPratama College of Engineering, San Jose State University, San Jose, California, USA Jason R. Tsao Department of Electrical Engineering, University of California, Los Angeles, California, USA Posted at http://www.engr.sjsu.edu/jtsao/papers/ISDSI-2009-BRT.ppt
Main Messages • Busway on street medians, dedicated except at intersections, is promising, but design and deploy it with caution. • Conventional design - two lanes plus two “platform lanes”: Taking away 3+ lanes from cars • A simple, efficient design: taking away only 2 lanes • A more efficient design: taking away only 1 lane • Focus: geometry and performance of a closed system; feasible geometry and promising performance • Development and proof of detailed operational rules for an open system being funded as phase II research, by California Department of Transportation
Bus Rapid Transit (BRT) with Dedicated Lanes in Median • Yes! Yes! Yet, No Space: • Two bus lanes throughout • Two “passenger lanes” as platforms at a bus stop • Or, “Empty-lane Syndrome” • Underutilization of dedicated bus lanes amid heavy car and other traffic • Particularly after taking car lanes away for buses • Why not Transit-Orientated Development (TOD)? • Chicken-and-egg Problem • Solutions: • Two-slanted-lanes BRT, at least • One-dedicated-lane BRT, as a start or an end. • Second-phase research funded again by California DOT on traffic-control algorithm and technology
Bus Rapid Transit with Two Dedicated Lanes:3 Lanes Taken from Car Use, at least (Berkeley)
Launching Bus Rapid Transit with Only One Dedicated Lane - Synopsis • Background and Motivation: • US Surface Transportation Infrastructure • US Transit Industry • Major Problems • At least 3 lanes taken away from car use • with Two Examples • An Efficient, Easy Solution: Only Two Lanes Taken Away • A More Efficient Solution Concept: Only One Lane Taken • Geometry; performance for a closed system; completed for California Department of Transportation (CalTrans) • Performance for an open system: being funded by CalTrans • Conclusion
Background and Motivation:US Surface Transportation Infrastructure • The National (Defense) Highway System: – Car-highway-centric People Mobility • 50-year design life (after WWII): demand and fuel assumptions • Now, end of design life or near • Car-based urban-suburban development • Economy • “Drunken-sailor” spending in last 8 years • Global competition • Barely sufficient funds for highway repair, given economy • Fossil fuel depletion and climate-change concerns • Trouble, for people mobility: • Complete reliance on (“addiction” to) fossil fuel; inability to expand highways and even disrepair; environmental concerns • Public transportation: after thought; chicken-and-egg problem, given the low population density induced by the car-based urban-suburban development • Transit: although one of few options, no space and no money • A larger potential danger: necessity of sudden paradigm change, due to fossil fuel, economy and demographical reasons
US Transit Industry • Less than 5% person-miles travelled • Capital cost: all federal subsidy • Operating cost: 25% from the fare box, on average • Miserable ridership: e.g., Valley Transportation Authority (Silicon Valley); 4.27 passenger miles travelled per vehicle-mile driven • Bus Rapid Transit (BRT) – “Light-rail with buses” • without dedicated lanes: marginal travel time improvement • with dedicated lanes: • high potential for travel-time reduction and reliability • very few existing (e.g., Lane County Transit of State of Oregon) or being planned (e.g., Alameda County Transit, in Berkeley-Oakland, California; see official pictures.)
Focus of Research • BRT with dedicated “right-of-way” in arterial median, except at intersections • Congested corridors with frequent left-turn lanes • Traffic signals supporting Transit Signal Priority (TSP) • More advanced technologies, e.g., automatic vehicle location (AVL), system control algorithms, driver-system communication, etc.
Major Problems for Conventional BRT/LR Geometric Designs • No space, for most congested corridors • “Empty-lane Syndrome” for those that have • How about transit-oriented development (TOC)? • Chicken-and-egg problem
Bus Rapid Transit with Two Dedicated Lanes:3 Lanes Taken from Car Use, at least (Berkeley)
Light Rail with Two Dedicated Lanes:3 Lanes Taken from Car Use, at least (VTA; Silicon Valley)
A Proposed Incremental Deployment(Backward Introduction) • Deployment Step 2: An Simple, Efficient Solution • Deployment Step 1: A More Efficient Solution
Comparison: w/o Station; 7 lanes Conventional Design Proposed Design (Step 2)
Comparison:with Station; 7 Lanes Conventional Design Proposed Design (Step 2)
One-dedicated-lane BRT • Dynamically reversible direction to accommodate two-way traffic • Crossing is the key. • Crossing using the spaces otherwise unused or underused for traffic purposes, e.g., currently landscaped median space • Two extremes: • Crossing only at a bus station • Crossing at any block sufficiently long
One-dedicated-lane BRT (Step 1):Section w/o Station, w/o Crossing Space
One-dedicated-lane BRT (Step 1):Section w/o Station, with Crossing Space
One-dedicated-lane BRT (Step 1):Section with Station and Crossing Space
One-dedicated-lane BRT (Step 1): Station and Crossing Space near Intersection; Multiple Configurations, e.g.,
One-Lane Bus Rapid Transit (Step 1):1 Lane Taken Effectively, Throughout
Performance Analysis: Closed System, with Crossing Only at Bus Station • Headway = 2 x section travel time • Different section lengths: speed control to achieve constant section travel time • Passenger activities: speed control to achieve constant section travel time • Technology support for monitoring bus traffic and achieving timely crossing • Additional Signage and possibly control to ensure safety
Performance Analysis for an Open System (to be reported separately) • Enabling schedule adherence • Crossing only available at a Bus Station: • Designing Signaling cycles for intersections • Transit signal priority to facilitate adherence to schedule • Crossing also available at any sufficiently long block • Catching up after delay and missed crossing
Conclusion • Busway on street medians, Dedicated except at intersections, is promising, but design and deploy it with caution. • Conventional design - two lanes plus two “platform lanes”: Taking away 3+ lanes from cars • A simple, efficient design: taking away only 2 lanes • A more efficient design: taking away only 1 lane • Focus: geometry and performance of a closed system; feasible geometry and promising performance • Development and proof of detailed operational rules for an open system being funded as phase II research, by California Department of Transportation