CE 353 Lab Weeks 9-12: Rail Design

Background

During the next 4 weeks, you will work with a team of 3 other students to plan and design (preliminary) a rail spur, which is to connect two sections of mainline track. While the lab uses a railroad example, most of the concepts investigated will be applicable to road design as well. To familiarize you with the terrain of the project area, we provide an image map with attached photos, taken of the area. The area is just northeast of Des Moines.

This clickable picture map shows the terrain views

There is also an aerial photo of the area uners consideration linked to leture 3.

It will be necessary to download a self-extracting zip file to your local PC. Follow the instructions below.

Download the self extracting zip file by clicking here When prompted, choose Save File..and save to the C:\User directory.
Then run rail-lab.exe by double clicking. This will explode files into a C:\user\rail-lab directory. As you work and especially after the day is over, save the files in the user\rail-lab directory to a your Iomega Zip disk.

Instructions for Mapbasic Program

A MapBasic program will be used to determine elevations (profile) for proposed alignments (plans). This is done by overlaying your proposed alignments (plans) over topographical contours (see instructions below). MapInfo is not a CAD package, so do not spend excessive time on trying to create exact drawings. The purpose of the MapInfo tool is to quickly allow you to assess the existing grade profile and its ability to fit an alignment meeting the requirements of the lab. Read ALL the requirements in the lab below before starting. Try three proposed alignments.

Fire up MapInfo. Command syntax is: Start>Programs>Transportation>MapInfo Pro
Then, run a mapbasic program that we wrote to open needed files and prepare a template for your alignment. Command syntax is: File>Run Mapbasic Program>profile.mbx (note: the mapbasic program is located in C:\user\rail-lab)

Some place on the map, draw an elipse (use elipse drawing tool of drawing menu). The elipse can be of any size.
Then, using the arrow pointing tool, double click the elipse you drew. You should specify the x and y radii to correspond to a circle of appropriate radius (minimum radius of curvature of rail line). The elipse will change into a circle, but may not look round due to the map projection used.
Make a copy of your circle (select the circle and use ctrl-c, ctrl-v). These two circles will be used to help you draw in your proposed alignment.
Place each circle tangent to the existing rail lines (one at the north end of your proposed alignment, and one at the south). If you wish to have a curve in between the two ends, you may make another copy of the circle.
Use the Polyline tool to draw a proposed alignment (Important: use the polyline tool and draw only one, continuous alignment, and DRAW THE ALIGNMENT FROM LEFT TO RIGHT. If you make a mistake, delete your alignment and redraw it.) Click once to begin the alignment, and once at each intermediate point. Double Click mouse when finished.
Delete the circles once you have drawn your alignment.
Find box with "rail" icon in the GIS tool box... and click on icon (note: it may be under another menu). The program will run for a while, and eventually create a profile for your plan.
The profile graph may now be exported to Excel for analysis. Export the "profile" table to .dbf format to use in Excel. Do this by selecting File, Save Copy As, and select the file type to be .dbf. This table contains your profile elevations and distances which you can use to plot existing and proposed profile. An example of how to use Excel to plot profiles is shown in a file trial.xls included in the exploded files in the User directory.

If you wish to assess another alignment, save the MapInfo table "Plan". "Plan" is the polyline of your alignment plan. Save the table "Plan" under another name such as "align1.tab" using "Save Copy As" (Important as the profile.mbx mapbasic program erases the table "Plan" each time it runs).
To re-examine a previously developed alignment (such as the one you saved in "align1.tab", first close all tables by selecting File, Close All. Then run the Mapbasic program (profile.mbx). Next, select File, Open Table and select the appropriate table (e.g., align1.tab). Select the alignment, then copy it (CTRL-C) and paste it (CRTL-V) to the editable layer (plan). Close the table "align1.tab" and continue as desired (e.g., print a map, change colors, run the rail icon, etc.)

Follow the criteria below to complete lab.

The old Chicago, Rock Island and Pacific (CR&P) Railroad near Berwick, Iowa is to be joined with the Chicago Northwestern route so the CRP line does not have to go all the way into Des Moines. Abandonment will permit more extensive development of land around the abandoned CRP in Des Moines. The instructor will show some slides of the area to demonstrate the challenges associated with the design. The following are design guides that the student is to follow:

Design speed of 35 mph.
Horizontal curvature limited to a maximum of 4º 00'.
Spirals of suitable length must be used to introduce all horizontal curvature.
Maximum grades of 1% are to be used unless the gradient exceeds this value at the point you begin or end the project.
Use a frog number of 8 (use the design drawing in the Illinois Central design spec appendix). Leave at least a 39' section of straight track after the frog, before you begin any spiral transistion.
Lines must not come in or take off from curved sections of track.
Cuts and fills should be minimized, but compared to the approximate cost of structures.
Use of existing bridges should be maximized.
Removal of houses and other structures should be avoided if possible.
Property acquisition parallel to property lines is preferred over diagonal crossings.
AREA specifications for vertical curve lengths on secondary lines must be followed.
Avoid non-90 degree road crossings
Approximate cut and fill quantities using the average end area method. You may assume flat grade in cross section for this purpose.
Provide two example cross section drawings (in these cases, you cannot assume flat grade in cross section). Draw in the grade lines (original and final) and ballast/track structure.
Estimate costs for rail, ties, ballast, structires and earthwork (roughly) for the three alternatives.
Provide for drainage. If you use culverts to do this, estimate flows roughly using q=cia (estimate drainage basin using MapInfo ... draw a polygon aound the drainage basin and double click the polygon to get the area). Make any other necessary assumptions to very roughly size culverts.
Provide for at grade road crossings (or under/overpasses if more cost effective). Crossbucks are cheap, but signalized crossings cost up to $100,000. See if you need signal control.
Prepare an alternatives matrix using at least cost, environmental, safety, social, grade categories. Note: some criteria may be qualitative, but you must come up with a commensurate way to compare alternatives.

Requirements

See score sheet

Plan Sheet

Bearings of all tangent lines.
Basic circular curve and spiral data.
Stationing for critical points such as PI, TS, SC, CS, and ST.
Calculated lengths are to be to the nearest 0.1 foot.

Profile Sheet

Grade line and ground line.
Stationing for vertical curve elements including PI, PVC, and PVT and their elevations. Calculated stations and elevations are to be to the nearest 0.1'. Gradients are to be to the nearest 0.1 percent.
Location of required drainage structures.
Profile of highway in the area of railroad crossings.

Report

The report will contain your calculations and a discussion of the considerations given to your specific route choice.
You need to justify why your alignment is preferred over other locations.
If you decide to change a basic guideline, you must argue for your decision.

Special Notes

Be careful with grades at the point you join the lines. The new track must have the same grade as the existing track in this area.
Neatness, grammar and style counts!