Chapter 2 Design Geometrics And Criteria

Topic #625-000-007Plans Preparation Manual, Volume 1January 1, 2017Chapter 2Design Geometrics and Criteria2.0General . 2-12.0.12.1Lanes . road-Highway Grade Crossing Near or WithinProject Limits . 2-3Travel Lanes and Auxiliary Lanes. 2-4Other Lane Widths . 2-5Ramp Traveled Way Widths . 2-6Pedestrian, Bicycle and Public Transit Facilities . 2-62.1.4.1 Pedestrian Facilities . 2-62.1.4.2 Bicycle Facilities . 2-72.1.4.3 Public Transit Facilities . 2-7Cross Slopes . 2-72.1.5.1 Hydroplaning Risk Analysis . 2-8Roadway Pavement . 2-112.1.6.1 Alternative Roadway PavingTreatments . 2-112.1.6.2 Maintenance Memorandum ofAgreement Requirements forPatterned Pavement . 2-13Transitions of Pavement Widths . 2-15Number of Lanes on the State Highway System . 2-15Medians . 2-162.2.12.2.22.2.3Median Width for Roadways . 2-16Median Policy for Multilane Facilities . 2-17Median Treatments on Bridges . 2-17Design Geometrics and Criteria2-i

Topic #625-000-007Plans Preparation Manual, Volume 12.3January 1, 2017Shoulders . 2-182.3.12.3.22.3.3Limits of Friction Course on Paved Shoulders . 2-26Shoulder Warning Devices (Rumble Strips) . 2-26Use of Curb . 2-272.4Roadside Slopes . 2-272.5Borders . 2-272.5.1Limited Access Facilities . 2-302.6Grades . 2-312.7Sight Distance . 2-342.8Curves . 2-372.8.12.8.2Horizontal Curves . 2-372.8.1.1 Supplemental Alignment Control(Mainline) . 2-372.8.1.2 Supplemental Alignment Control(Intersections) . 2-412.8.1.3 Roadway Transitions . 2-41Vertical Curves . 2-422.9Superelevation . 2-442.10Vertical Clearance . 2-502.10.12.10.22.10.32.10.4Vertical Clearance Over Water . 2-58Horizontal Waterway Clearance . 2-59Regulatory Agency Requirements . 2-59Airspace Obstructions . 2-602.11Bridge Sections . 2-622.12Bridge Railings and Separators . 2-67Design Geometrics and Criteria2-ii

Topic #625-000-007Plans Preparation Manual, Volume 12.13Intersections . 2-672.13.12.13.22.13.32.14January 1, 2017Roundabouts . 2-672.13.1.1 Truck Apron. 2-682.13.1.2 Lighting . 2-692.13.1.3 Landscaping . 2-692.13.1.4 Pavement Markings . 2-69Queue Length for Unsignalized Intersections . 2-70Offset Left Turn Lanes . 2-70Interchanges and Median Openings/Crossovers . 2-722.14.12.14.22.14.32.14.4Limited Access Right of Way Limits at Interchanges 2-72Median Openings at Interchanges . 2-74Ramp Widths. 2-75Crossovers on Limited Access Facilities . 2-762.15Lighting Criteria . 2-822.16High-Speed Urban and Suburban Arterial Highways . .82.16.92.16.102.16.11Design Speed. 2-83Curbs . 2-83Pedestrian and Bicycle Facilities . 2-83Medians . 2-83Shoulders . 2-84Friction Course . 2-84Border Width . 2-85Grades . 2-85Horizontal Curves . 2-85Superelevation . 2-86Lateral Offset. 2-86Design Geometrics and Criteria2-iii

Topic #625-000-007Plans Preparation Manual, Volume 1January 1, 2017TablesTable 2.1.1Table 2.1.2Table 2.1.3Table 2.1.4Table 2.2.1Table 2.3.1Table 2.3.2Table 2.3.3Table 2.3.4Table 2.5.1Table 2.5.2Table 2.5.3Table 2.6.1Table 2.6.2Table 2.6.3Table 2.6.4Table 2.7.1Table 2.7.2Table 2.8.1aTable 2.8.1bTable 2.8.2aTable 2.8.2bLane Widths . 2-4Lane Widths - Special. 2-5Ramp Widths . 2-6Maximum Algebraic Difference in Cross Slope atTurning Roadway Terminals. 2-10Median Widths . 2-16Shoulder Widths and Cross Slopes Freeways . 2-19Shoulder Widths and Cross Slopes Arterials Divided . 2-20Shoulder Widths and Cross Slopes Arterials Undivided . 2-21Shoulder Widths and Cross Slopes –Collectors Divided and Undivided . 2-22Highways with Flush Shoulders. 2-28Highways with Curb or Curb and Gutter inUrban Areas . 2-29Limited Access Facilities . 2-30Maximum Grades . 2-32Maximum Change in Grade WithoutVertical Curves . 2-32Criteria for Grade Datum . 2-33Grade Criteria for Curb and Gutter Sections. 2-33Minimum Stopping Sight Distance . 2-35Minimum Passing Sight Distance . 2-36Maximum Deflections without Horizontal Curves . 2-39Maximum Deflection for Through Lanesthrough Intersections . 2-39Length of Horizontal Curves . 2-40Arc Length (in feet) of Compound Curves withOne-Half/Double Radii - Turning Roadways . 2-40Design Geometrics and Criteria2-iv

Topic #625-000-007Plans Preparation Manual, Volume 1Table 2.8.3Table 2.8.4Table 2.8.5Table 2.8.6Table 2.9.1Table 2.9.2Table 2.9.3Table 2.9.4Table 2.10.1Table 2.10.2Table 2.10.3Table 2.14.1January 1, 2017Maximum Curvature of Horizontal Curve(Using Limiting Values of "e" and "f"). 2-40Maximum Horizontal Curvature Using NormalCross Slopes (-0.02) . 2-41Minimum Lengths of Crest Vertical CurvesBased on Stopping Sight Distance . 2-42Minimum Lengths of Sag Vertical CurvesBased on Stopping Sight Distance andHeadlight Sight Distance . 2-43Superelevation Rates for Rural Highways,Urban Freeways and High Speed UrbanHighways (e max 0.10) . 2-45Superelevation Rates for Urban Highwaysand High Speed Urban Streets (emax 0.05) . 2-47Superelevation Transition Slope Rates forRural Highways, Urban Freeways andHigh Speed Urban Highways . 2-49Superelevation Transition Slope Rates for UrbanHighways and High Speed Urban Streets . 2-49Minimum Vertical Clearances for New Bridges. 2-57Minimum Vertical Clearances for New Signand Signal Structures . 2-57FAA Notification Requirements . 2-61Ramp Widths - Turning Roadways . 2-75Design Geometrics and Criteria2-v

Topic #625-000-007Plans Preparation Manual, Volume 1January 1, 2017FiguresFigure 2.1.1Figure 2.3.1.AFigure 2.3.1.BFigure 2.3.2Figure 2.9.1Figure 2.9.2Figure 2.10.1Figure 2.10.2Figure 2.10.3Figure 2.10.4.AFigure 2.10.4.BFigure 2.10.5Figure 2.11.1Figure 2.11.2Figure 2.11.3Figure 2.11.4Figure 2.13.1Figure 2.13.2Figure 2.13.3Standard Pavement Cross Slopes . 2-9Shoulder Superelevation . 2-23Special Shoulder Superelevation . 2-24Typical Paving Under Bridge . 2-25Superelevation Rate For Rural Highways,Urban Freeways and High Speed UrbanHighways (e max 0.10). 2-46Superelevation Rates for Urban Highwaysand High Speed Urban Streets (emax 0.05) . 2-48Clearances – Rural and Urban Interstates(Freeways), Arterials and Collectors, withProjected 20-Year ADT of 1500 or Greater . 2-51Clearances – Rural Arterials and Collectors withProjected 20-Year ADT of Less than 1500 . 2-52Clearances – Urban Arterials and Collectors(Without Curb and Gutter) with Projected20-Year ADT of Less than 1500 . 2-53Clearances – Urban Arterials and Collectors(Curb and Gutter) 45 mph – Elevation of Bridge . 2-54Clearances – Urban Arterials and Collectors (Curband Gutter) 45 mph – Section through Bridge . 2-55Clearances – Urban Arterials and Collectors(Curb and Gutter) with Traffic Barrier . 2-56Partial Bridge Sections * . 2-63Bridge Section * . 2-64Partial Bridge Sections * . 2-65Bridge Section * . 2-66Standard Truck Apron Design . 2-68Roundabout Approach Arrow . 2-69Typical Opposing Left Turns (22’ Medianwith Negative 10’ Offset) . 2-70Design Geometrics and Criteria2-vi

Topic #625-000-007Plans Preparation Manual, Volume 1Figure 2.13.4Figure 2.13.5Figure 2.14.1Figure 2.14.2Figure 2.14.3Figure 2.16.3January 1, 2017Typical Opposing Left Turns (22’ Medianwith Negative 1’ Offset) . 2-71Left Turn Offset Guidelines . 2-72Crossovers on Limited Access Facilities –6 or More Lanes . 2-79Crossovers on Limited Access Facilities –4 Lanes . 2-80Median Barrier Opening for Crossovers onLimited Access Facilities . 2-81Superelevation Rates for High-Speed Urban andSuburban Sections . 2-86Design Geometrics and Criteria2-vii

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Topic #625-000-007Plans Preparation Manual, Volume 1January 1, 2017Chapter 2Design Geometrics and Criteria2.0GeneralThe implementation of design criteria is outlined in the following text.1.Design Criteria: The design criteria presented in this manual are intended asthe principal source of criteria for the design of new construction or majorreconstruction projects on the Florida State Highway System.These criteria are presented by subject for major design elements as fixed valuesor a range of acceptable values as defined by qualifiers.Where design criteria appear in the Design Standards, they will be consistentwith the criteria in this manual. In addition, some criteria will remain in the otherchapters of this manual. When conflicts are discovered, they should be broughtto the attention of the State Roadway Design Engineer or State StructuresDesign Engineer, as applicable, for resolution.Modification for Non-Conventional Projects:Delete the last sentence of the above paragraph and replace with the following:Where conflicts exist, the EOR must select the criteria proven to result in bettersafety performance.On reconstruction projects, existing project features which were constructed tomeet minimum metric design criteria, but are mathematically slightly less thanequivalent minimum English design criteria, do not require Design Exceptions orDesign Variations to remain.Design criteria for Resurfacing, Restoration, and Rehabilitation (RRR) are presentedin Chapter 25 of this Volume and are applicable only on programmed RRR projects.Modification for Non-Conventional Projects:Delete the sentence above and see RFP for requirements.Facilities on the Strategic Intermodal System (SIS) are subject to specialstandards and criteria for number of lanes, design speed, access, level of serviceand other requirements.Design Geometrics and Criteria2-1

Topic #625-000-007Plans Preparation Manual, Volume 1January 1, 2017Design SIS and Emerging SIS Highway Intermodal Connectors on the StateHighway System (SHS) in accordance with the SIS criteria contained in thismanual. SIS and Emerging SIS Highway Intermodal Connectors on the localsystem (non-SHS) should also be designed in accordance with the SIS criteriacontained in this manual, but the District may allow the use of the Manual ofUniform Minimum Standards for Design, Construction and Maintenance forStreets and Highways (commonly known as the "Florida Greenbook"), TopicNo. 625-000-015 depending on project specifics, with approval by the DistrictDesign Engineer.Modification for Non-Conventional Projects:Delete the last sentence of the above paragraph and see RFP for requirements.Design Criteria for roads that are not part of the State Highway System should beobtained from the Florida Greenbook.Modification for Non-Conventional Projects:Delete the last sentence.2.Design Controls: Design controls are characteristics and conditions that influenceor regulate the selection of the criteria for project standards. It is the designer'sresponsibility to recognize and apply those controls applicable to the project.3.Design Standards: The specific values selected from the design criteriabecome the design standards for a design project. These standards will beidentified and documented by the designer.4.Project Parameters: The properties or specific conditions with limits whichrequire modification of design standards within these limits. The designer isresponsible for establishing and documenting any project parameters and theirlimits, as part of the justification for deviations from project standards.Modification for Non-Conventional Projects:Delete the last sentence of the above paragraph.Many design standard considerations are related directly to the design speed, includingvertical and horizontal geometry and required sight distances. The minimum designvalues are very closely related to traffic safety and cannot be compromised without anapproved Design Exception or Design Variation. See Chapter 23 of this Volume.Design Geometrics and Criteria2-2