Transportation Report Essay Research Paper INTRODUCTIONRoadway Engineers

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Transportation Report Essay, Research Paper INTRODUCTION Roadway Engineers and Consultants, Inc. was employed by the North Carolina Department of Transportation to design a roadway connecting Alexandria and Old Statesville Road, and also a Park-n-Ride facility along the Norfolk-Southern Railroad. Due to the addition of the Charlotte-Mecklenburg Transit Plan, which will locate a rail transit station near Alexandria and Old Statesville Road, the surrounding roads will become more populated, therefore lowering the level of service below the acceptable limits. To alleviate the traffic congestion and raise the level of service of the surrounding roads, a roadway was proposed to accommodate the increased trip generation produced by the Rail Transit Station. The roadway was to be

built connecting Alexandria and Old Statesville Road. This new roadway will compensate for the increased trip generation due to the proposed Rail Transit Station and will raise the level of service to an acceptable limit. The proposed roadway will connect Old Statesville Road and Alexandria. A topographic map is located in Appendix C, which illustrates the exact location of the roadway. The roadway will be classified as a commercial collector street with a design speed of 40 mph. The roadway will include two 12 feet lanes, curb & gutter, and a 16 foot median. The proposed roadway design will include a total right of way of 80 feet. Due to the layout of the two existing roads being connected, a horizontal curve was designed to compensate for the unparallel layout, while

keeping intersections at both ends perpendicular to the existing roads. A vertical curve was also needed due to the elevation changes along the proposed roadway layout. The vertical curve was designed to minimize the amount of fill material needed to complete the project. This was accomplished by equalizing the amount of cut and fill, thus reducing the cost of the project. The proposed Park-n-Ride facility will provide access to the Rail Transit Station. A detailed plan view of the facility is located in Appendix E, which displays the exact layout. The Park-n-Ride facility will include a loading and unloading platform, 300-space parking lot, and bus unloading area. A more detailed description of the Park-n-Ride facility and the proposed roadway will be discussed later in the

report. DESIGN Roadway Design The scope of this design focuses on the design plans requested by the NC DOT. The requested items were: + Plan view 1 =50 + Profile view 1 =50 horizontal 1 =5 vertical + Typical cross-section + Earthwork cross-sections and computation of cut/fill + Topographical map showing alignment + Horizontal and Vertical curve calculations The NC DOT also specified the following variables: Road Classification Commercial Collector Design Speed 40 mph Max. superelevation/preferred 4% / 0% Sidewalk 5 wide each side Lanes 2 12 Curb & Gutter 2 -6 Median 16 Right-of-way 80 * A detailed plan and cross-sectional view of the roadway is located in Appendix A and D, respectively. Horizontal Curve Design The horizontal curve was designed with a 800 foot radius and a 40

miles per hour design speed with relatively little superelevation. The roadway totaled 1322 feet in length with a horizontal curve length of 461 feet. The results of the calculations to layout the horizontal curve are displayed in the following table. A detailed diagram of the methods used to calculate the results are shown in Appendix F. Appendix A contains the plan view of the roadway layout. Description of Data Results Tangent Length 237 feet Curve Length 461 feet Central Angle 33 degrees Degree of Curvature 7.16 Vertical Curve The vertical curve designed is a Type II crest curve, which is explained in Appendix G. The vertical curve was placed so that the inflection point was located at 700 feet in elevation. A more detailed chart of the vertical curve calculations is also