Continuous Flow Intersection, J-Turn 19

Total Page:16

File Type:pdf, Size:1020Kb

Continuous Flow Intersection, J-Turn 19 Alternative Intersections/Interchanges: Informational Report (AIIR) PUBLICATION NO. FHWA-HRT-09-060 APRIL 2010 Research, Development, and Technology Turner-Fairbank Highway Research Center 6300 Georgetown Pike McLean, VA 22101-2296 FOREWORD Today’s transportation professionals, with the limited resources available to them, are challenged to meet the mobility needs of an increasing population. At many highway junctions, congestion continues to worsen, and drivers, pedestrians, and bicyclists experience increasing delays and heightened exposure to risk. Today’s traffic volumes and travel demands often lead to safety problems that are too complex for conventional intersection designs to properly handle. Consequently, more engineers are considering various innovative treatments as they seek solutions to these complex problems. This report covers four intersection and two interchange designs that offer substantial advantages over conventional at-grade intersections and grade-separated diamond interchanges. It also provides information on each alternative treatment covering salient geometric design features, operational and safety issues, access management, costs, construction sequencing, environmental benefits, and applicability. The six alternative treatments covered in this report are displaced left- turn (DLT) intersections, restricted crossing U-turn (RCUT) intersections, median U-turn (MUT) intersections, quadrant roadway (QR) intersections, double crossover diamond (DCD) interchanges, and DLT interchanges. Raymond Krammes Acting Director, Office of Safety Research and Development Notice This document is disseminated under the sponsorship of the U.S. Department of Transportation in the interest of information exchange. The U.S. Government assumes no liability for the use of the information contained in this document. The U.S. Government does not endorse products or manufacturers. Trademarks or manufacturers’ names appear in this report only because they are considered essential to the objective of the document. Quality Assurance Statement The Federal Highway Administration (FHWA) provides high-quality information to serve Government, industry, and the public in a manner that promotes public understanding. Standards and policies are used to ensure and maximize the quality, objectivity, utility, and integrity of its information. FHWA periodically reviews quality issues and adjusts its programs and processes to ensure continuous quality improvement. TECHNICAL DOCUMENTATION PAGE 1. Report No. 2. Government Accession No. 3. Recipient’s Catalog No. FHWA-HRT-09-060 4. Title and Subtitle 5. Report Date Alternative Intersections/Interchanges: Informational Report (AIIR) April 2010 6. Performing Organization Code 7. Author(s) 8. Performing Organization Report No. Warren Hughes, Ram Jagannathan, Dibu Sengupta, and Joe Hummer Project 37769.19 9. Performing Organization Name and Address 10. Work Unit No. (TRAIS) Vanasse Hangen Brustlin, Inc. (VHB) 8300 Boone Blvd., Suite 700 11. Contract or Grant No. Vienna, VA 22182-2626 DTFH61-05-D-00024 (VHB) Subconsultants: North Carolina State University; Persaud Lyon, Inc.; Task T-06-016 University of Missouri-Rolla 12. Sponsoring Agency Name and Address 13. Type of Report and Period U.S. Department of Transportation Technical Report Federal Highway Administration Office of Safety Informational Report 1200 New Jersey Ave., SE August 2006 to July 2009 Washington, DC 20590 14. Sponsoring Agency Code FHWA 15. Supplementary Notes The Federal Highway Administration (FHWA) Office of Safety Research and Development managed this study. The FHWA Office of Safety Research and Development Contract Task Order Manager was Dr. Joe Bared. Project focus group members contributed significantly to document organization, content, and exhibits. They included Tom Hicks and Saed Rahwanji from the Maryland State Highway Administration; Debbie Self from the Charlotte Department of Transportation; Ed Rice and Jon Obenberger from the U.S. Department of Transportation; Louis Thibault from the U.S. States Access Board; Robert Copp and Jerry Champa from the California Department of Transportation; and Mike Cynecki from the City of Phoenix. In addition, many FHWA staff members participated as focus group members and/or provided comments throughout the project including Neil Spiller, James Colyar, John Halkias, Wei Zhang, Tamara Redmon, Fred Ranck, Brian Chandler, Mary Stringfellow, William Prosser, and Scott Wainwright. The research team is grateful to James Young and the Ohio Department of Transportation for providing the real-world intersection example used in chapter 10. 16. Abstract Today’s transportation professionals are challenged to meet the mobility needs of an increasing population with limited resources. At many highway junctions, congestion continues to worsen. Drivers, pedestrians, and bicyclists experience longer delays and greater exposure to risk. Today’s traffic and safety problems are more complex and complicated. Conventional intersection/ interchange designs are sometimes found to be insufficient to mitigate transportation problems. Consequently, many engineers are investigating and implementing innovative treatments in an attempt to think outside the box. This report covers four intersection designs and two interchange designs that may offer additional benefits compared to conventional at-grade intersections and grade- separated diamond interchanges. The six alternative treatments covered in this report are displaced left-turn (DLT) intersections, restricted crossing U-turn (RCUT) intersections, median U-turn (MUT) intersections, quadrant roadway (QR) intersections, double crossover diamond (DCD) interchanges, and DLT interchanges. The information presented in this report provides knowledge of each of the six alternative treatments including salient geometric design features, operational and safety issues, access management issues, costs, and construction sequencing and applicability. 17. Key Words 18. Distribution Statement Alternative intersections, Alternative interchanges, CFI, XDL, DDI, DLT, No restrictions. DCD, MUT, Median U-turn, Diverging diamond, Displaced left-turn, Super street, Continuous flow intersection, J-turn 19. Security Classif. (of this report) 20. Security Classif. (of this page) 21. No. of Pages 22. Price Unclassified Unclassified 340 Form DOT F 1700.7 (8-72) Reproduction of completed pages authorized SI* (MODERN METRIC) CONVERSION FACTORS APPROXIMATE CONVERSIONS TO SI UNITS Symbol When You Know Multiply By To Find Symbol LENGTH in inches 25.4 millimeters mm ft feet 0.305 meters m yd yards 0.914 meters m mi miles 1.61 kilometers km AREA in2 square inches 645.2 square millimeters mm2 ft2 square feet 0.093 square meters m2 yd2 square yard 0.836 square meters m2 ac acres 0.405 hectares ha mi2 square miles 2.59 square kilometers km2 VOLUME fl oz fluid ounces 29.57 milliliters mL gal gallons 3.785 liters L ft3 cubic feet 0.028 cubic meters m3 yd3 cubic yards 0.765 cubic meters m3 NOTE: volumes greater than 1000 L shall be shown in m3 MASS oz ounces 28.35 grams g lb pounds 0.454 kilograms kg T short tons (2000 lb) 0.907 megagrams (or "metric ton") Mg (or "t") TEMPERATURE (exact degrees) oF Fahrenheit 5 (F-32)/9 Celsius oC or (F-32)/1.8 ILLUMINATION fc foot-candles 10.76 lux lx fl foot-Lamberts 3.426 candela/m2 cd/m2 FORCE and PRESSURE or STRESS lbf poundforce 4.45 newtons N lbf/in2 poundforce per square inch 6.89 kilopascals kPa APPROXIMATE CONVERSIONS FROM SI UNITS Symbol When You Know Multiply By To Find Symbol LENGTH mm millimeters 0.039 inches in m meters 3.28 feet ft m meters 1.09 yards yd km kilometers 0.621 miles mi AREA mm2 square millimeters 0.0016 square inches in2 m2 square meters 10.764 square feet ft2 m2 square meters 1.195 square yards yd2 ha hectares 2.47 acres ac km2 square kilometers 0.386 square miles mi2 VOLUME mL milliliters 0.034 fluid ounces fl oz L liters 0.264 gallons gal m3 cubic meters 35.314 cubic feet ft3 m3 cubic meters 1.307 cubic yards yd3 MASS g grams 0.035 ounces oz kg kilograms 2.202 pounds lb Mg (or "t") megagrams (or "metric ton") 1.103 short tons (2000 lb) T TEMPERATURE (exact degrees) oC Celsius 1.8C+32 Fahrenheit oF ILLUMINATION lx lux 0.0929 foot-candles fc cd/m2 candela/m2 0.2919 foot-Lamberts fl FORCE and PRESSURE or STRESS N newtons 0.225 poundforce lbf kPa kilopascals 0.145 poundforce per square inch lbf/in2 *SI is the symbol for the International System of Units. Appropriate rounding should be made to comply with Section 4 of ASTM E380. (Revised March 2003) ii TABLE OF CONTENTS CHAPTER 1. INTRODUCTION ................................................................................................ 1 CHAPTER 2. DISPLACED LEFT-TURN INTERSECTION ................................................. 7 2.1 INTRODUCTION....................................................................................................... 7 2.2 GEOMETRIC DESIGN CONSIDERATIONS ..................................................... 12 2.3 ACCESS MANAGEMENT CONSIDERATIONS ................................................ 17 2.4 TRAFFIC SIGNALIZATION TREATMENTS .................................................... 20 2.4.1 Signal Design ............................................................................................... 22 2.4.2 Signing and Marking.................................................................................... 34 2.5 ACCOMMODATION OF PEDESTRIANS, BICYCLISTS, AND TRANSIT USERS ..........................................................................................................
Recommended publications
  • Manual on Uniform Traffic Control Devices Manual on Uniform Traffic
    MManualanual onon UUniformniform TTrafficraffic CControlontrol DDevicesevices forfor StreetsStreets andand HighwaysHighways U.S. Department of Transportation Federal Highway Administration for Streets and Highways Control Devices Manual on Uniform Traffic Dotted line indicates edge of binder spine. MM UU TT CC DD U.S. Department of Transportation Federal Highway Administration MManualanual onon UUniformniform TTrafficraffic CControlontrol DDevicesevices forfor StreetsStreets andand HighwaysHighways U.S. Department of Transportation Federal Highway Administration 2003 Edition Page i The Manual on Uniform Traffic Control Devices (MUTCD) is approved by the Federal Highway Administrator as the National Standard in accordance with Title 23 U.S. Code, Sections 109(d), 114(a), 217, 315, and 402(a), 23 CFR 655, and 49 CFR 1.48(b)(8), 1.48(b)(33), and 1.48(c)(2). Addresses for Publications Referenced in the MUTCD American Association of State Highway and Transportation Officials (AASHTO) 444 North Capitol Street, NW, Suite 249 Washington, DC 20001 www.transportation.org American Railway Engineering and Maintenance-of-Way Association (AREMA) 8201 Corporate Drive, Suite 1125 Landover, MD 20785-2230 www.arema.org Federal Highway Administration Report Center Facsimile number: 301.577.1421 [email protected] Illuminating Engineering Society (IES) 120 Wall Street, Floor 17 New York, NY 10005 www.iesna.org Institute of Makers of Explosives 1120 19th Street, NW, Suite 310 Washington, DC 20036-3605 www.ime.org Institute of Transportation Engineers
    [Show full text]
  • First Class Overloading Via Insersection Type Parameters⋆
    First Class Overloading via Insersection Type Parameters? Elton Cardoso2, Carlos Camar~ao1, and Lucilia Figueiredo2 1 Universidade Federal de Minas Gerais, [email protected] 2 Universidade Federal de Ouro Preto [email protected], [email protected] Abstract The Hindley-Milner type system imposes the restriction that function parameters must have monomorphic types. Lifting this restric- tion and providing system F “first class" polymorphism is clearly desir- able, but comes with the difficulty that inference of types for system F is undecidable. More practical type systems incorporating types of higher- rank have recently been proposed, that rely on system F but require type annotations for the definition of functions with polymorphic type parameters. However, these type annotations inevitably disallow some possible uses of higher-rank functions. To avoid this problem and to pro- mote code reuse, we explore using intersection types for specifying the types of function parameters that are used polymorphically inside the function body, allowing a flexible use of such functions, on applications to both polymorphic or overloaded arguments. 1 Introduction The Hindley-Milner type system [9] (HM) has been successfuly used as the basis for type systems of modern functional programming languages, such as Haskell [23] and ML [20]. This is due to its remarkable properties that a compiler can in- fer the principal type for any language expression, without any help from the programmer, and the type inference algorithm [5] is relatively simple. This is achieved, however, by imposing some restrictions, a major one being that func- tion parameters must have monomorphic types. For example, the following definition is not allowed in the HM type system: foo g = (g [True,False], g ['a','b','c']) Since parameter g is used with distinct types in the function's body (being applied to both a list of booleans and a list of characters), its type cannot be monomorphic, and this definition of foo cannot thus be typed in HM.
    [Show full text]
  • Disjoint Polymorphism
    Disjoint Polymorphism João Alpuim, Bruno C. d. S. Oliveira, and Zhiyuan Shi The University of Hong Kong {alpuim,bruno,zyshi}@cs.hku.hk Abstract. The combination of intersection types, a merge operator and parametric polymorphism enables important applications for program- ming. However, such combination makes it hard to achieve the desirable property of a coherent semantics: all valid reductions for the same expres- sion should have the same value. Recent work proposed disjoint inter- sections types as a means to ensure coherence in a simply typed setting. However, the addition of parametric polymorphism was not studied. This paper presents Fi: a calculus with disjoint intersection types, a vari- ant of parametric polymorphism and a merge operator. Fi is both type- safe and coherent. The key difficulty in adding polymorphism is that, when a type variable occurs in an intersection type, it is not statically known whether the instantiated type will be disjoint to other compo- nents of the intersection. To address this problem we propose disjoint polymorphism: a constrained form of parametric polymorphism, which allows disjointness constraints for type variables. With disjoint polymor- phism the calculus remains very flexible in terms of programs that can be written, while retaining coherence. 1 Introduction Intersection types [20,43] are a popular language feature for modern languages, such as Microsoft’s TypeScript [4], Redhat’s Ceylon [1], Facebook’s Flow [3] and Scala [37]. In those languages a typical use of intersection types, which has been known for a long time [19], is to model the subtyping aspects of OO-style multiple inheritance.
    [Show full text]
  • Roundabout Planning, Design, and Operations Manual
    Roundabout Planning, Design, and Operations Manual December 2015 Alabama Department of Transportation ROUNDABOUT PLANNING, DESIGN, AND OPERATIONS MANUAL December 2015 Prepared by: The University Transportation Center for of Alabama Steven L. Jones, Ph.D. Abdulai Abdul Majeed Steering Committee Tim Barnett, P.E., ALDOT Office of Safety Operations Stuart Manson, P.E., ALDOT Office of Safety Operations Sonya Baker, ALDOT Office of Safety Operations Stacey Glass, P.E., ALDOT Maintenance Stan Biddick, ALDOT Design Bryan Fair, ALDOT Planning Steve Walker, P.E., ALDOT R.O.W. Vince Calametti, P.E., ALDOT 9th Division James Brown, P.E., ALDOT 2nd Division James Foster, P.E., Mobile County Clint Andrews, Federal Highway Administration Blair Perry, P.E., Gresham Smith & Partners Howard McCulloch, P.E., NE Roundabouts DISCLAIMER This manual provides guidelines and recommended practices for planning and designing roundabouts in the State of Alabama. This manual cannot address or anticipate all possible field conditions that will affect a roundabout design. It remains the ultimate responsibility of the design engineer to ensure that a design is appropriate for prevailing traffic and field conditions. TABLE OF CONTENTS 1. Introduction 1.1. Purpose ...................................................................................................... 1-5 1.2. Scope and Organization ............................................................................... 1-7 1.3. Limitations ...................................................................................................
    [Show full text]
  • Chapter 10 Grade Separations and Interchanges
    2005 Grade Separations and Interchanges CHAPTER 10 GRADE SEPARATIONS AND INTERCHANGES 10.0 INTRODUCTION AND GENERAL TYPES OF INTERCHANGES The ability to accommodate high volumes of traffic safely and efficiently through intersections depends largely on the arrangement that is provided for handling intersecting traffic. The greatest efficiency, safety, and capacity, and least amount of air pollution are attained when the intersecting through traffic lanes are grade separated. An interchange is a system of interconnecting roadways in conjunction with one or more grade separations that provide for the movement of traffic between two or more roadways or highways on different levels. Interchange design is the most specialized and highly developed form of intersection design. The designer should be thoroughly familiar with the material in Chapter 9 before starting the design of an interchange. Relevant portions of the following material covered in Chapter 9 also apply to interchange design: • general factors affecting design • basic data required • principles of channelization • design procedure • design standards Material previously covered is not repeated. The discussion which follows covers modifications in the above-mentioned material and additional material pertaining exclusively to interchanges. The economic effect on abutting properties resulting from the design of an intersection at-grade is usually confined to the area in the immediate vicinity of the intersection. An interchange or series of interchanges on a freeway or expressway through a community may affect large contiguous areas or even the entire community. For this reason, consideration should be given to an active public process to encourage context sensitive solutions. Interchanges must be located and designed to provide the most desirable overall plan of access, traffic service, and community development.
    [Show full text]
  • SIMULATION of DIFFERENT INTERSECTION DESIGN for IMPROVING TRAFFIC FLOW with FACTORS CONSIDERING LOCATION, POPULATION and DRIVER EXPECTANCY Sourabh Kumar Singh Dr
    Science, Technology and Development ISSN : 0950-0707 SIMULATION OF DIFFERENT INTERSECTION DESIGN FOR IMPROVING TRAFFIC FLOW WITH FACTORS CONSIDERING LOCATION, POPULATION AND DRIVER EXPECTANCY Sourabh Kumar Singh Dr. Anil kunte Associate Professor, Research Scholar, Associate Professor, Department of Civil Department of Civil Department of Civil Engineering Engineering, Shri JJT Engineering, Shri JJT Noida International University University University Dr. Paritosh Srivastava Abstract: In today’s economic growth the vehicular traffic is increasing day by day, which leads to failure of intersections before their time period. To increase the efficiency of these failed intersections the engineers added lanes to the existing major and minor roads, but this method do not give results which it used to deliver in the past, hence other methods were adopted. So to increase the efficiency and fulfil the criteria for successful intersection ,to cape with it several intersection are designed which are unconventional in nature like jug handle, bow tie, continuous flow intersection and median u turn which are very effective in increasing green time on highway and minor roads. The software used in this study is Auto- cad for planning and drawing purpose which can be used in sim-traffic software which will be used for simulation purpose of the traffic flow on different designs of intersections. The factors which are considered in this study are -location of town centre, population of the zone and driver expectancy. The final conclusion of this study is that continuous flow intersection provides the best results when the traffic is increased. The construction cost is least in median u turn and giving maximum result than all other intersections.
    [Show full text]
  • The Gibraltar Highway Code
    P ! CONTENTS Introduction Rules for pedestrians 3 Rules for users of powered wheelchairs and mobility scooters 10 Rules about animals 12 Rules for cyclists 13 Rules for motorcyclists 17 Rules for drivers and motorcyclists 19 General rules, techniques and advice for all drivers and riders 25 Road users requiring extra care 60 Driving in adverse weather conditions 66 Waiting and parking 70 Motorways 74 Breakdowns and incidents 79 Road works, level crossings and tramways 85 Light signals controlling traffic 92 Signals by authorised persons 93 Signals to other road users 94 Traffic signs 96 Road markings 105 Vehicle markings 109 Annexes 1. You and your bicycle 112 2. Vehicle maintenance and safety 113 3. Vehicle security 116 4. First aid on the road 116 5. Safety code for new drivers 119 1 Introduction This Highway Code applies to Gibraltar. However it also focuses on Traffic Signs and Road Situations outside Gibraltar, that as a driver you will come across most often. The most vulnerable road users are pedestrians, particularly children, older or disabled people, cyclists, motorcyclists and horse riders. It is important that all road users are aware of The Code and are considerate towards each other. This applies to pedestrians as much as to drivers and riders. Many of the rules in the Code are legal requirements, and if you disobey these rules you are committing a criminal offence. You may be fined, or be disqualified from driving. In the most serious cases you may be sent to prison. Such rules are identified by the use of the words ‘MUST/ MUST NOT’.
    [Show full text]
  • Continuous Flow Intersection, Parallel Flow Intersection, and Upstream Signalized Crossover
    Comparison of Three Unconventional Arterial Intersection Designs: Continuous Flow Intersection, Parallel Flow Intersection, and Upstream Signalized Crossover Seonyeong Cheong, Saed Rahwanji, and Gang-Len Chang Abstract— This research is aimed to evaluate and world have adopted many conventional measures, including compare the operational performance of three signal planning and double left-turn lanes, for alleviating this unconventional intersections: Continuous Flow problem [1]. The using of these conventional measures are Intersection (CFI), Parallel Flow Intersection (PFI) and limited as the modifications of intersection design, such as Upstream Signalized Crossover (USC). For this purpose, widening interchanges and building bypasses, are expensive various experimental designs, including traffic conditions, and disruptive [1]. In contrast, the unconventional arterial geometric features and signal plans, were set and the intersection design (UAID) is one of the methods that can average delays were compared for movements of efficiently reduce the congestion with less cost as compare through-only traffic and left-turn-only traffic. From the with the conventional measures. General principles of results of analysis, all three unconventional intersections operation and management strategies of the UAID include: 1) outperformed conventional one and among the emphasis on through traffic movements along the arterial; 2) unconventional intersections, CFI outperformed the reduction in the number of signal phases (e.g. left-turn arrow others except for some traffic conditions. In the balanced phase); and 3) reduction in the number of intersection conflict traffic condition scenario, at the low traffic volume level, points [2]. These principles allow the UAID to reduce the the average delays of through traffic for PFI were smaller traffic congestion at the intersection and improve the traffic than that of CFI and very similar at the moderate traffic safety.
    [Show full text]
  • Transportation Network Plan Middleton, WI
    Report Transportation Network Plan City of Middleton, WI December 2006 Report for City of Middleton, Wisconsin Transportation Network Plan Prepared by: Traffic Associates LLC and STRAND ASSOCIATES, INC.® 910 West Wingra Drive Madison, WI 53715 www.strand.com December 2006 Approved by Middleton City Council November 21, 2006 TABLE OF CONTENTS Page No. or Following SECTION 1–INTRODUCTION AND EXECUTIVE SUMMARY 1.01 Overview.................................................................................................... 1-1 1.02 Executive Summary................................................................................... 1-3 SECTION 2–EXISTING TRANSPORTATION SYSTEM 2.01 Existing Transportation System................................................................. 2-1 2.02 Traffic Data Collection................................................................................ 2-14 2.03 Existing Conditions Modeling..................................................................... 2-16 SECTION 3–FUTURE CONDITIONS 3.01 Future Traffic Forecasting.......................................................................... 3-1 3.02 Future Conditions Traffic Operations Modeling ......................................... 3-4 3.03 Prioritization of Future Motor Vehicle Needs ............................................. 3-6 SECTION 4–SOLUTION TYPES 4.01 Transportation Solutions............................................................................ 4-1 4.02 Traffic Management Perspective ..............................................................
    [Show full text]
  • Technical Report Documentation Page Z2
    Technical Report Documentation Page 1. Report No. 2. Government Accession No. 3. MDOT Project Manager RC-1554 Jason Firman, P.E. 4. Title and Subtitle 5. Report Date Developing a Congestion Mitigation Toolbox September 30, 2011 6. Performing Organization Code Texas Transportation Institute 7. Author(s) 8. Performing Org. Report No. Jason A. Crawford, P.E.; Todd B. Carlson, AICP; William L. 1554 Eisele, Ph.D., P.E.; and Beverly T. Kuhn, Ph.D., P.E. 9. Performing Organization Name and Address 10. Work Unit No. (TRAIS) Texas Transportation Institute The Texas A&M University System 11. Contract No. TAMU 3135 2009-0661 College Station, TX 77843-3135 11(a). Authorization No. Z2 12. Sponsoring Agency Name and Address 13. Type of Report & Period Covered Michigan Department of Transportation Final Report 14. Sponsoring Agency Code 15. Supplementary Notes 16. Abstract Increased traffic congestion is a result of many sources including increasing demand and lagging supply. Responding to increasing congestion, agencies from the federal government to local townships have turned to congestion management, or mitigation. Congestion mitigation is delivered through a variety of techniques. The Michigan Department of Transportation (MDOT) recognized a need to assist state and local agency partners to identify potential congestion mitigation strategies and improve collaboration. Texas Transportation Institute (TTI) researchers developed “A Michigan Toolbox for Mitigating Congestion.” The team conducted several tasks in development of the Toolbox. The TTI team reviewed and consulted previous congestion toolboxes for strategy identification, toolbox elements, and toolbox style. The research team implemented a survey of metropolitan planning organizations throughout the country to gather agency experiences with congestion mitigation strategies.
    [Show full text]
  • GUIDELINES for TIMING and COORDINATING DIAMOND November 2000 INTERCHANGES with ADJACENT TRAFFIC SIGNALS 6
    Technical Report Documentation Page 1. Report No. 2. Government Accession No. 3. Recipient's Catalog No. TX-00/4913-2 4. Title and Subtitle 5. Report Date GUIDELINES FOR TIMING AND COORDINATING DIAMOND November 2000 INTERCHANGES WITH ADJACENT TRAFFIC SIGNALS 6. Performing Organization Code 7. Author(s) 8. Performing Organization Report No. Nadeem A. Chaudhary and Chi-Leung Chu Report 4913-2 9. Performing Organization Name and Address 10. Work Unit No. (TRAIS) Texas Transportation Institute The Texas A&M University System 11. Contract or Grant No. College Station, Texas 77843-3135 Project No. 7-4913 12. Sponsoring Agency Name and Address 13. Type of Report and Period Covered Texas Department of Transportation Research: Construction Division September 1998 – August 2000 Research and Technology Transfer Section 14. Sponsoring Agency Code P. O. Box 5080 Austin, Texas 78763-5080 15. Supplementary Notes Research performed in cooperation with the Texas Department of Transportation. Research Project Title: Operational Strategies for Arterial Congestion at Interchanges 16. Abstract This report contains guidelines for timing diamond interchanges and for coordinating diamond interchanges with closely spaced adjacent signals on the arterial. Texas Transportation Institute (TTI) researchers developed these guidelines during a two-year project funded by the Texas Department of Transportation. 17. Key Words 18. Distribution Statement Diamond Interchanges, Capacity Analysis, Traffic No restrictions. This document is available to the Signal Coordination, Traffic Congestion, Signalized public through NTIS: Arterials National Technical Information Service 5285 Port Royal Road Springfield, Virginia 22161 19. Security Classif.(of this report) 20. Security Classif.(of this page) 21. No. of Pages 22. Price Unclassified Unclassified 50 Form DOT F 1700.7 (8-72) Reproduction of completed page authorized GUIDELINES FOR TIMING AND COORDINATING DIAMOND INTERCHANGES WITH ADJACENT TRAFFIC SIGNALS by Nadeem A.
    [Show full text]
  • Community Meeting for Mary Avenue Grade Separation, Aug. 10, 2017
    Caltrain Grade Separation Feasibility Study Mary Avenue Railroad Crossing Community Meeting August 10, 2017 Agenda • Meeting format review • Goals and context • Mary Avenue options Feedback • Q and A • Next steps • Adjourn 2 Caltrain Grade Separations Project Goals Improve Safety (LUTE Policy 24, 36, 40, 41, 42, 46) Enhance Reduce Ped/Bike Traffic Delay Access (LUTE Policy 32, 42) (LUTE Policy 24, 33, 36, 41) 4 Project Context 60,000 50,000 40,000 30,000 Average Daily Ridership Daily Average 20,000 76 trains 92 trains 114 trains (2003) (2016) +80-106 HSR (2040) Caltrain Grade Separation – VTA Program Description Sunnyvale has 2 of the 8 at grade crossings VTA criteria include cost efficiency and Complete Streets 6 Screening Alternatives Screening • Establish rail and road criteria Alternatives • Identify existing conditions • Develop cursory design of alternatives • Identify impacts and constraints Impacts • Bring results to community Variants of • Identify feasible alternatives Screening • Develop variants to minimize impacts Alternatives • Engage community for input 7 Initial Screening Alternatives 8 At-grade Railroad Crossing Grade Separated Crossing - Overpass At-grade Railroad Crossing Grade Separated Crossing - Underpass Design Criteria Roadway Railroad Grades 4.75% 1.2% max Design speed 30 - 45 mph 79 mph for shoofly (temp rail) Based on posted speed 110 mph for final condition plus 5 mph Bridge depth 5’ 6.75’ Supporting roadway Supporting railroad Vertical clearance Underpass Overpass 15.5’ over roadway 27’ over railroad Roadway
    [Show full text]