CE 436/536 – ROADWAY DESIGN April 1 , 2008

1. CE 436/536 – ROADWAY DESIGN April 1, 2008 • Review Design Project • Storm Drainage Concepts for Urban and Rural Roadway Design • Reallocation of grading as follows: • Attendance 5% • Participation 10% • Homework (incl. design prj.) 35% • Mid Term Exam 20% • Final Exam 30%

2. Remainder of Semester • April 1 • Review project progress • Roadway drainage • Urban drainage design considerations • Rural drainage design considerations • April 8 • Review project progress • Fundamentals of traffic flow – Chapter 5 • April 15 • Review project progress • Capacity and Level of Service – Chapter 6 • April 22 • Present design project outcomes • Overview of Inroads roadway design software • Signalized intersections – Chapter 7 • Trip generation and traffic modeling – Chapter 8 • April 29 • Closed Week - Review of course materials • May 6 • Final Exam – the final exam will be a take home report

3. Design Project Review Horizontal Alignment Route Selection Curve Selection Super Rate Selection (matching the super rate to the curve) Stationing (picking a beginning station greater than 0+00) Let’s look at some examples of conceptual horizontal geometry layout that I did with Inroads on the CAD.

4. Design Project Review Next Steps: Create profile Maximum grade = 7% Minimize the earthwork Select vertical curves of the appropriate length based on K value and algebraic difference in grades Requires iteration to find best solution

5. Design Project Kickoff Purpose of Design Project – to provide you with an opportunity to design a roadway using the concepts you have learned. Goals of Design Project – become familiar with selecting design standards, routing an alignment that is efficient and cost effective, produce 3-D drawings that describe your design, and summarize your effort through preparing a cost estimate and writing a design narrative. Last week we chose teams for the project. They are as follows: Greydon(C)Venky(C)Anisa(C) KrisAllamMartin Gretchen SwarupValeriya The team captains are designated by a “C”. Captains are really nothing special, but I thought each team should have one?!

6. Design Project Kickoff • Design Products – with the givens you have you will prepare the following: • Horizontal alignment showing all tangent, curve, and superelevation information • Vertical alignment (profile) showing all tangent and curve information • Typical section drawings • Cross-sections showing earthwork, and clear zone design/issues • Summary of quantities for major items • Cost estimate for construction using quantity summary for pavement, aggregate base, and earthwork • Design narrative/report summarizing your design methodology, standards, etc. • I would like you to use a CAD drafting program of some type if possible – let’s talk about this – do you have access to CAD? What kind???? • I can post the electronic version of this mapping on the Mosfet site if you can use it?

7. Design Project Kickoff Given Information: Design a highway with two lanes in each direction and appropriate shoulder widths (AASHTO) Posted speed is to be 45 mph The anticipated volume on this highway will be 8000 vehicles per day The asphalt will be 6 inches thick and the aggregate base material will be 12 inches thick A subgrade geotextile will be used Clear zone should comply with the Roadside Design Guide Chapter 3 for the given design speed Where clear zone can not be met due to extreme terrain, consider guardrail or barrier or a combination of the two Keep environment in mind while designing

8. Design Project Kickoff Given Information: Design a highway with one lane in each direction and appropriate shoulder widths (AASHTO) Posted speed is to be 45 mph The anticipated volume on this highway will be 8000 vehicles per day The asphalt will be 6 inches thick and the aggregate base material will be 12 inches thick A subgrade geotextile will be used Clear zone should comply with the Roadside Design Guide Chapter 3 for the given design speed Where clear zone can not be met due to extreme terrain, consider guardrail or barrier or a combination of the two Keep environment in mind while designing Let’s review the mapping and talk more about what to do

9. Design Project Kickoff Recommended Schedule: By/during 4/1 class recommend having the horizontal alignment pretty much selected and typical section(s) drawn up. By /during 4/8 class recommend having vertical alignment (profile) finalized and drawn. By/during 4/15 class recommend having the cross-sections nearly completed. Modifications to the typical sections may be needed depending on what you find with your cross-sections. By the 8/22 class recommend have the quantities calculated, cost estimate completed, and design narrative completed for the presentation.

10. Storm Drainage related to Roadway Design • Roadway Design – Storm drainage design could be a class of its own. • Overview of your experience with hydraulics and hydrology. • Storm drainage design is a significant and critical component of almost every roadway design project regardless of the size of the project or the topographical setting (urban, rural, suburban, etc.). • Why is storm drainage so important? • Protect the roadway • Safely convey storm water away from private property to prevent flooding or concentration of water. • Roadways can and do change the natural drainage patterns. These changes have to be taken into account to ensure they don’t flood new areas. • Storm water is also an environmental issue. It can contain high levels of pollutants from the roadway surface (heavy metals, etc.). Treatment of the water is often required before it can be discharged into a stream or river. • Roadways create new impervious surfacing, thereby increasing the rate at which water concentrates.

11. Storm Drainage related to Roadway Design • Why is storm drainage so important? • Roadways create new impervious surfacing, thereby increasing the rate at which water concentrates as compared to the natural ground. • When the time of concentration decreases the volume of water ultimately increases often requiring retention and/or detention along with quality treatment.

12. Storm Drainage related to Roadway Design • Brief overview of roadway storm drainage methodologies. • What storm interval should you design for? • Rational Method (Q= CiA) very commonly used with a composite “C” value calculated. Intensity from IDF curves based on storm interval. Area is the contributing area. • Rural design is typically a series of open ditches and culverts • Urban design is typically a series of inlets, pipes, and manholes • Let’s look at some examples. • Blacktail Ridge (rural transforming to urban/suburban) • Birch Creek (rural)

13. Storm Drainage related to Roadway Design

14. Storm Drainage related to Roadway Design

15. Storm Drainage related to Roadway Design

16. Storm Drainage related to Roadway Design Urban storm drainage considerations: Inlet types Inlet spacing Curb and gutter geometry Gutter flow depth and width (spread) Flow velocity in gutter and pipes Inlet bypass on grades Maintenance Material types Treatment and detention/retention Flow into roadway system from beyond the roadway area (common) Area inlets

17. Storm Drainage related to Roadway Design Rural storm drainage considerations: Ditches (ditch depth to protect subgrade) Cross-culverts Maintenance Material types Treatment and detention/retention Flow into roadway system from beyond the roadway area (common) Area inlets