| 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 displayed in Appendix G.
Earthwork
The cut and fill requirements are based on the vertical curve placement. The vertical curve was carefully placed to minimize fill material needed for the project. The cut and fill diagrams are displayed in Appendix B. The areas were taken every hundred feet and then cut and fill were calculated for the section using the following equation:
V = (.5L(Ai+Aj))
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The volumes of each section were then summed and total fill requirements were obtained. The total fill needed to complete the proposed roadway is 125 cubic yards, which assumes the compaction ratio of the fill material is 85 percent and will be compacted to 100 percent using various methods.
Park-n-Ride Facility
The Charlotte-Mecklenburg Transit Plan proposed a rail transit line along the Northfolk-Southern Rail Road. A Transit Station will be located near Alexandria Road and Old Statesville Road. A Park-n-Ride facility was designed to accommodate passengers entering and exiting the Transit Station. The facility will include a bus stop that allows four busses to simultaneously load and unload, 300-space parking for passenger vehicles, handicapped parking, and bicycle parking. The docking platform for the train will be long enough to manage four transit cars per stop.
The Park-n-Ride facility is divided into two areas, the train-side and the roadside. The train-side includes all facilities located on the side of the road next to the train station. These facilities include the bus stop, handicapped parking, and the bicycle parking. They will be located directly adjacent to the train station. The 300 vehicle parking lot, on the other hand, will be located across Alexandria. To cross the street, three alternatives were proposed and a decision matrix was employed to choose the best alternative.
The decision matrix is as follows:
Cross Walk Tunnel Bridge
Cost 30% 10 (3.0) 5 (1.5) 3 (.9)
Safety 40% 6 (2.4) 8 (3.2) 9 (3.6)
Practicality 15% 9 (1.35) 6 (.9) 8 (1.2)
Delay Traffic 15% 4 (.6) 10 (1.5) 8 (1.2)
Total 7.35 7.1 6.9
Scale: 10 = very effective, 1 = not effective
Although safety ranks low for the cross walk; the benefits of cost effectiveness and practicality clearly outweigh the disadvantages. Therefore, the cross walk was chosen as the best design alternative. The cross walk will be signaled for pedestrian safety, though traffic delay will be greater. The entire Park-n-Ride facility will be connected to both the proposed roadway and Alexandria by driveways, one each. Drainage, lighting, planting, and a 50 foot buffer will be provided along the road. Sidewalks will also be included. For a detailed drawing of the Park-n-Ride Facility, refer to Appendix E.
Conclusions
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. The surrounding roadways affected by the new facilities will be alleviated by the introduction of the proposed road. Roadway Engineers and Consultants, Inc. will maximize the level of service to the surrounding roads, and create a user friendly environment to the vehicles entering and exiting the new Park-n-Ride Facility, while moving through traffic along smoothly. The Park-n-Ride Facility will accommodate
passengers entering and exiting the Transit Station. Roadway Engineers and Consultants, Inc. are confident in our work and believe the proposed designs will benefit the surrounding areas. Therefore, it is recommended that the proposal should be implemented and the project finished, which will lead to more business growth in the surrounding areas and also less congestion on the streets.
EXECUTIVE SUMMARY
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 totaled 1322 feet in length with a horizontal curve length of 461 feet. The radius of curvature was set at 800 feet and a 40 miles per hour design speed. A vertical curve was also created for the proposed road due to the elevation change from start to end. The vertical curve was placed so that the inflection point was located at 700 feet in elevation. The placement of the vertical curve also affected cut and fill requirements. The vertical curve was carefully placed to minimize fill material needed for the project, thus reducing the cost of the project.
The Park-n-Ride facility will be divided into two areas, the train-side and the roadside. The train-side includes all facilities located on the side of the road next to the train station. These facilities include the bus stop, handicapped parking, and the bicycle parking. They will be located directly adjacent to the train station. The 300-space parking lot, on the other hand, will be located across Alexandria. A cross walk was needed to safely progress pedestrians across the street. The cross walk will be signaled for pedestrian safety, though traffic delay will be greater. The entire Park-n-Ride facility will be connected to both the proposed roadway and Alexandria by driveways, one each. Drainage, lighting, planting, and a 50 foot buffer will be provided along the road. Sidewalks will also be included.
The surrounding roadways affected by the new facilities will be alleviated by the introduction of the proposed road. Roadway Engineers and Consultants, Inc. will maximize the level of service to the surrounding roads, and create a user friendly environment to the vehicles entering and exiting the new Park-n-Ride Facility, while moving through traffic along smoothly. The Park-n-Ride Facility will accommodate
passengers entering and exiting the Transit Station.
Roadway Engineers and Consultants, Inc. are confident in our work and believe the proposed designs will benefit the surrounding areas. Therefore, it is recommended that the proposal should be implemented and the project finished, which will lead to more business growth in the surrounding areas and also less congestion on the streets.
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