The following are three projects my Highway Design team worked on. Building on the horizontal and vertical alignment concepts provided in Transportation Engineering I and outlines provided by the AASHTO Green Book, the advanced Highway Design class enabled me to focus on new and different design elements such as freeways and freeway interchanges, local streets, and unconventional intersections.
Objective: East-west travel through southern Wake County is hampered by a lack of arterials south of Tryon Road. To remedy that gap, planners have proposed a “Cary-Garner Parkway” which would run from the current end of Cary Parkway at Holly Springs Road to US-401 between the US-70 junction and the railroad crossing in Garner. Provide a preliminary alignment for the Parkway.
Controls: Provide an arterial with as few intersections as possible, a 60 mph design speed, an emax of 0.08, two lanes in each direction, and a minimum median width 28 feet.
Solution: We developed an approximately 6 mile alignment with 11 horizontal curves that minimized intersections and housing impacts while keeping cut and fill approximately equal.
WAKE FOREST RD. INTERCHANGE
Objective: The intersection of Wake Forest Rd. and I-440 has significant traffic buildup during peak hours, enough to merrit an interchange re-build. Using traffic counts, propose an alternative interchange design that would serve this intersection better.
Solution: Looking at the traffic counts provided, we were able to pinpoint traffic buildup to the fault of left turns from vehicles exiting I-440. We proposed a Diverging Diamond Interchange that would redirect traffic to the opposite side of the road on the overpass, allowing left turns to flow freely. Synchro analysis showed this to be a drastic improvement.
US 421 CORRIDOR STUDY
Objective: For the portion of US 421 that passes through Dunn, NC, propose a smarter design with traffic calming features and access managment by considering physical treatments and existing conditions. Collect information, generate alternatives, and recommend the best case scenario in a presentation in front of the Council Members of Dunn at the Dunn Community Center.
Solution: After developing multiple alternatives, our best case scenario was a complete build-out of our access management alternatives, road dieting alternatives, and traffic redistribution techniques that included right-in/right-out and direction left-over installations at key intersections along US 421. Traffic lights were both reduced and adjusted for better flow through downtown, while in-town traffic was directed to Broad St.
The presentation of this project to the City Board of Dunn was an amazing experience and I am very glad to have had such an opportunity.