Geometric Design Lab - Lab 09
Define a Vertical Profile using GEOPAK

Copyright 2009 by Dr. Thomas W. Rioux
Students taking this course may print one copy of this document for their personal class use.


Objective:   Learn vertical alignment design using GEOPAK.

Activity:   Start MicroStation and create a 2D design file "Z:\MicroStation\lab_09.dgn" using the seed file "Z:\MicroStation\train2d.dgn"; Start GEOPAK, set the standard GEOPAK user preferences for this class, and set the standard COGO preferences for this class; Create a GEOPAK Project named lab_09 using Job Number 09 with Subject of "Vertical Curve" and set Coordinate Geometry for Temporary Visualization; Store the Points; Create the centerline chain; Draw the centerline chain and station the centerline chain; Define the vertical profile; Draw the vertical profile; Place a landscape oriented rectangle centered around the vertical curve in 8.5" by 11" proportion; Place the title "Lab Assignment 09" at the top center and your name, class name, and assignment due date in the bottom center; Place a fence from the rectangle and plot the drawing; Measure the width of pavement under the crest curve which would have a clearance of 15.0 feet and write your answer on the plot; Exit MicroStation; and Reboot the computer.

Background:   A vertical profile defines the elevation of the roadway using sag curves, crest curves, and tangent sections.   Design objectives for vertical profiles are (1) to minimize the maximum grade, (2) to provide adequate lateral and vertical clearance over other roadway features at grade separations, and (3) to provide safe stopping sight distance at all points along the vertical profile.    A vertical curve has a Vertical Point of Curve (VPC), a Vertical Point of Intersection (VPI), and a Vertical Point of Tangency (VPT).

Normally, the Existing Ground Profile of the centerline chain is obtained from a Digital Terrain Model (DTM) and drawn where the temporary visualization of the vertical profile is placed so that the user can see the elevation of the existing ground while defining the vertical profile.   The Design and Computation Manager visualization for the vertical profile is normally placed at the same location as the temporary visualization of the vertical profile so that the user can see the elevation of the existing ground.

A.   Start MicroStation and create a 2D design file "Z:\MicroStation\lab_09.dgn" using the seed file "Z:\MicroStation\train2d.dgn".

B.   Start GEOPAK, set the standard GEOPAK user preferences for this class, and set the standard COGO preferences for this class.

C.   Create a GEOPAK Project named lab_09 using Job Number 09 with Subject of "Vertical Curve" and set Coordinate Geometry for Temporary Visualization.

D.   Store Point Number 1 at an X of 5000 and a Y of 5000 and store Point Number 2 at a Bearing of N 90 E and a Distance of 2000 feet from Point Number 1.   Minimize the Coordinate Geometry dialog box.   In MicroStation Window 1, choose the Fit View icon.   The 2 points should be visible.

E.   Create the centerline chain with a Chain Name of CH1, Begin at 0+00, the 1st segment is Point 1, and the 2nd segment is Point 2.   Minimize the Coordinate Geometry dialog box.   In MicroStation Window 1, choose the Fit View icon.   The 2 points and the chain should be visible.

F.   Draw the centerline chain and station the centerline chain.

F.1.   Draw the centerline chain using the Design and Computation Manager using the Texas Department of Transportation (TxDOT) GEOPAK parameter file "Z:\MicroStation\txengd.ddb" selecting FEATURES then DRAFTING STANDARDS, then Alignments, then BL Baseline Horizontal Alignment, and finally Draw Plan & Profile for Job 09 setting Element Type to Chains, Curve Data to on, all other options to off, and Label Scale to 200 for Chain CH1.

F.2.   Station the centerline chain setting Element Type to Stationing, Tick Marks to on, Tick Marks Stations to on, PC/PT/TS/CS/SC/ST Labels to on, PI Labels to on, Small Ticks to Ticks Right; Labels Right, Large Ticks to Ticks Both; Labels Right, Control Point Labels to As Per Preferences, and Label Scale to 200 for Chain CH1.

F.3.   In MicroStation Window 1, choose the Fit View icon.   The centerline chain and stationing should be visible.

G.   Define the vertical profile with the crest curve VPI at station 10+00.00 and elevation 25 feet with an initial length of sag curve (L sag) of 360 feet and an initial length of crest curve (L crest) of 1250 feet.

G.1.   Choose Applications -> ROAD -> Geometry -> Layout Profiles (VPI Based).

G.2.   In the Settings dialog box, set Job Number to 09, set Operator Code to your 2 initials, set PGL Chain to CH1, set Horizontal Scale to 100.000000, set Vertical Scale to 10.000000, set Reference Station to 0+00.00, set Reference Elevation to 0.000000, set X to 5000.000000, set Y to 5600.000000, and press the OK push button (this will position the temporary visualization for the vertical profile at 5000,5600 with a 100:10 vertical exaggerated scale).

G.3.   In the Profile Generator dialog box, choose File -> K Value Table.   In the K Values dialog box, choose File -> Open.  In the K Value dialog box, choose KValues_2001english.kvl and press the Open push button.   In the K Values dialog box, press the OK push button.   K Values Table: KValues_2001english.kvl should appear on the top line of the dialog box.

G.4.   In the Profile Generator dialog box, set Station to 0+00.00 (the beginning of the chain), set Elevation to 0.00, and press the Enter key.

G.5.   In the Profile Generator dialog box, press the Insert >> push button.

G.6.   In the Profile Generator dialog box in the VPI 2 group, set Station to the calculated value of 10+00.00 (crest curve center) minus 6+25.00 (L crest / 2.0) minus 1+80.00 (L sag / 2.0) = 1+95.00, set Elevation to 0.00, and press the Enter key.

G.7.   In the Profile Generator dialog box, press the Insert >> push button.

G.8.   In the Profile Generator dialog box in the VPI 3 group, set Station to 10+00.00, set Elevation to 25.00, and press the Enter key.

G.9.   In the Profile Generator dialog box, press the Insert >> push button.

G.10.   In the Profile Generator dialog box in the VPI 4 group, set Station to the calculated value of 10+00.00 (crest curve center) plus 6+25.00 (L crest / 2.0) plus 1+80.00 (L sag / 2.0) = 18+05.00, set Elevation to 0.00,  and press the Enter key.

G.11.   In the Profile Generator dialog box, press the Insert >> push button.

G.12.   In the Profile Generator dialog box in the VPI 5 group, set Station to 20+00.00 (the ending of the chain), set Elevation to 0.00, and press the Enter key.

G.13.   In MicroStation Window 1, choose the Fit View icon.   The centerline chain, centerline stationing, and vertical profile temporary visualization should be visible.

G.14.   In the Profile Generator dialog box, choose File -> Save Profile As.

G.15.   In the Save Profile As dialog box, set Profile to PROF1, set File to j09o<your_2_initials>.inp, and press the OK push button.   This is a precautionary measure so if you make a mistake in the rest of the Step G instructions, you can re-load the profile saved at this point.

G.16.   In the Information dialog box stating "Profile PROF1 stored", press the OK push button.

G.17.   In the Profile Generator dialog box, press the Previous button in the lower left corner 3 times until the VPI 2 group is in the center (see pictures for Step G.6).

G.18.   In the Profile Generator dialog box in the Vertical Curve group, choose Symmetrical Vertical Curve and set Speed to 55.

G.19.   In the Profile Generator dialog box, press the Next push button in the lower right corner (VPI 3 should be in the center) (see pictures for Step G.8).

G.20.   In the Profile Generator dialog box in the Vertical Curve group, choose Symmetrical Vertical Curve, set Speed to 70, notice "Overlap 140.65" under the Vertical Curve group name (this means that the beginning VPC of the vertical curve at VPI 3 starts 140.65 feet before the ending VPT of the vertical curve at VPI 2; this is an error condition), set Speed to 55, and notice that the "Overlap 140.65" message disappears.

G.21.   In the Profile Generator dialog box, press the Next push button in the lower right corner (VPI 4 should be centered) (see pictures for Step G.10).

G.22.   In the Profile Generator dialog box in the Vertical Curve group, choose Symmetrical Vertical Curve and set Speed to 55.

G.23.   In the Coordinate Geometry dialog box, set Redefine to on .

G.24.   In the Profile Generator dialog box, choose File -> Save Profile, in the alert dialog box stating that "Profile PROF1 redefined", press the OK push button.

G.25.   In the Coordinate Geometry dialog box, set Redefine to off.

G.26.   In MicroStation Window 1, choose the Fit View icon.   The centerline chain, centerline stationing, and vertical profile temporary visualization should be visible.

G.27.   Close the Profile Generator dialog box and the temporary visualization of the vertical profile will be deleted (see pictures for Step F.3).   If you get an Alert box asking "Do you want to save your profile?", press the No push button.

H.   Draw the vertical profile.

H.1.   Draw the vertical profile using the Design and Computation Manager using the Texas Department of Transportation (TxDOT) GEOPAK parameter file "Z:\MicroStation\txengd.ddb" selecting FEATURES, then PROFILES, then PROFILES 100 H 10 V SCALE, then PGL/Offset Design, then MAINLANE PGL Mainlane PGL or Offset Design, and finally Draw Plan & Profile for Job 09.

H.2.   In the Draw Plan & Profile dialog box, set Element Type to Profiles, set Label Scale to 200, set VPI Labels to on using From VPI and Circle, set Horizontal Axis Labels to on, set Vertical Axis Labels to on, set V. C. Incremental Elevations to off, set V. C. Parameters to off, set Grades Labels to on using + and -, set K value to on, set External Length to on, set Station Equation to off with No Gaps, set VPC/VPT Label to on, set Stopping Sight Distance to off, and in the Select Profile group, select PROF1 once.

H.3.   In the Profile dialog box, in the Plot Settings group, set Horizontal Scale to 100, set Vertical Scale to 10, set Beginning Station to 0+00.00, set Ending Station to 20+00.00, set Strip Grade Increment to empty (nothing set); in the Profile Reference Point group, set Reference Station to 0+00.00, set Reference Elevation to 0.0000, set X to 5000.000000, set Y to 5600.000000; in the Profile Cell group set PGL Chain to CH1, and press the OK push button (this will position the Design and Computation Manager visualization for the vertical profile at 5000,5600 with a 100:10 vertical exaggerated scale).

H.4.   Close the Draw Plan & Profile dialog box and close the Design and Computation Manager dialog box.

H.5.   In the Coordinate Geometry dialog box, choose Tools -> Clear Visualized Elements (Temporary) and File -> Exit.   In MicroStation Window 1, choose the Fit View icon.

I.   Place a landscape oriented rectangle centered around the vertical curve in 8.5" by 11" proportion (2330 feet by 1800 feet) with level of Level 1 (level=Level 1), color of white (color=0), style of solid (style=0), and weight of 0 (weight=0).

J.   Place the title "Lab Assignment 09" at the top center and your name, class name, and assignment due date in the bottom center using a text height, text width, and text line spacing of 50 feet with font of 3  (font=ENGINEERING), justification of Center Center, level of Level 1 (level=Level 1), color of white (color=0), style of solid (style=0), and weight of 0 (weight=0).

K.   Place a fence from the rectangle placed in Step I and plot the drawing using ENGR-SC2-Laser-2 and options for Fence, Monochrome, Letter, Landscape, a Scale of 250 ft / in, and Settings -> Print Attributes -> Fence boundary off and Print border on.

Define a Vertical Profile using GEOPAK Plot

L.   Thinking of the vertical curve as an overpass with a freeway going underneath with the top of pavement at elevation zero, measure the width under the crest curve which would have a vertical clearance of 15.0 or more feet relative to the freeway and write your answer on the plot.

M.   Exit MicroStation.

N.   Reboot the computer.

Geometric Design Lab Spring 2011 web page

 

Latest Update: 11 Feb 2011 02:43 PM