Highlighter Fall 2015

Spring 2016 | 3 the pavement section by installing a woven geotextile in the base material, overbuilding the structural course and raising the profile of the road. The second part of the RRR process in Florida is to “enhance highway safety”. This starts with a thorough review of the 13 AASHTO Controlling Design Elements: design speed, lane width, shoulder width, bridge width, structural capacity, vertical clearance, grade, cross slope, superelevation, horizontal alignment, vertical alignment, stopping sight distance, and lateral offset (or clearzone). Like most states, AASHTO sets the minimum criteria and FDOT has developed more stringent standards for some of these design elements. We attempt to correct as many deficient elements as budget, schedule, and right of way will allow. Other safety considerations on RRR projects include the following: „ „ Intersection operations including signalization needs, pavement markings, turning radii, channelization, and ADA needs „ „ Drainage concerns where there is a flooding history or potential for hydroplaning „ „ Pedestrian, Bicycle, and Transit needs „ „ At-grade railroad crossings „ „ Aesthetics and Landscaping „ „ Highway lighting „ „ Highway Traffic Control Devices „ „ Bridges and associated design elements of a bridge „ „ Roadway Safety Hardware such as guardrail „ „ Ancillary Structures associated with signs, signals, lighting and ITS This is a lot of design elements to review. The PPM also allows for engineering judgement on when these elements should be corrected with the RRR project or can remain. To supplement the PPM and provide consistent results across the state and among the numerous consultants, FDOT has develop RRR Practical Design Guidelines which have basically develop three (3) lists; items to always correct on a RRR project, items that do not need to be corrected on a RRR project, and items that are left up to the discretion of the FDOT Project Manager. Let me give you an example of how we incorporated safety on a RRR project. One of the most challenging resurfacing projects I have worked on was along Alternate US 19 (SR 595) from Whisper Lake Road to Harry Street in Pinellas County. This is the main thorough fare that connects the beach communities of Ozona, Palm Harbor, and Crystal Beach. It has heavy pedestrian and bicycle use and at the time of the RRR project did NOT have continuous sidewalk and bike lanes. The main safety objectives were: „ „ To “fill in the gaps” in the sidewalk „ „ Add bicycle lanes „ „ Make sure all intersections were ADA compliant „ „ Eliminate areas of standing water that were causing hydroplaning „ „ Correct intersection deficiencies at DeSoto Blvd and Bee Pond Road I use this term lightly, but let’s talk about the “easy” stuff first. Bicycle lanes were achieved by utilizing existing paved shoulders, adding paved shoulders when necessary, and by reducing the lane widths in curb and gutter sections. Curb cut ramps, signals, and pedestrian features were upgraded at all intersections. The ponding water and hydroplaning was corrected by correcting the cross slope with overbuild, and cleaning out pipes and swales. DeSoto Blvd originally tied into Alternate US 19 at a 12-degree angle. We were able to realign this roadway within the existing right of way to achieve a 90-degree angle. The challenge came when we tried to “fill in the gaps” in the sidewalk. This is an older beach community where most of the resident and businesses had open driveways along their entire frontage. How do you get the pedestrians safely across these wide (most were greater than 50 feet) driveways? You don’t! The driveways needed to be modified to bring them into compliance with current access management standards. After reviewing the crash data at these wide driveway locations, it was determined that 15 properties warranted some type of driveway modification. When we started drawing up the modified driveways, it became apparent that a large majority of the properties were actually using the FDOT right of way as their parking lot and without continuing to do so, these properties could not stay in business. FDOT entered into agreements with the properties owners to lease back the FDOT right of way. The end result not only provided a safe path for pedestrians and bicyclists, it also improved the overall aesthetics of this corridor essentially giving a tired beach community road a face lift. If maintaining our roadways was simple, we would not have pot holes and there would be virtually no accidents. Unfortunately we are not there yet. On all roads, whether it is resurfacing to extend its pavement life or adding sidewalk for pedestrians, there is always a challenge in the design that makes our jobs as engineers fun and interesting. Now if I could figure out a way to make cleaning her room fun and interesting for my teenager… that would be an accomplishment. n Tabatha Carlton,PE Senior Project Manager Alt US 19 | BEFORE Alt US 19 | AFTER “The end result not only provided a safe path for pedestrians and bicyclists, it also improved the overall aesthetics of this corridor essentially giving a tired beach community road a face lift.”

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