Tutorial 22
In this exercise
you will
¨
Position a
proposed dam wall on a natural surface contour plan
¨
Extract a
Profile and cross sections along the proposed centreline
¨
Enter the
design level of the dam wall
¨
Calculate
the volume of material in the wall
¨
Store design
coordinates of the dam wall, and form a combined surface
¨
Calculate
the storage capacity of the dam
Start
Ezicad_Premium, and use File, Open, to access Job “DAM” which will be in the
folder Ezicad_Premium\tutor.
Now Pull down
Contour, and Form the Model and then Calculate and Save Contours and then use
F8 to turn off the triangles, to get a screen as shown below.
Some preliminary
investigation has been done.
The design
coordinates of the end points of the proposed wall have been decided on, and
are listed below.
West End: E- 739
N- 862
East End: E-
983 N- 792
Our first task
will be to add these points to the job.
Pull down the
Points Menu and select Add Points to change the cursor to a cross.
Now position your
cursor somewhere within the surface and press the left mouse button.
The
Add/Edit/Query screen will appear and you need to decide what Point Number to
add in.
It is a good
practice to start new ranges of points on even hundred or thousand values, and
in this case we will assign points for the wall from Point 600.
Enter in Point
600 and then the relevant coordinates for the west end point.
Now repeat the
process to add Point 601 on the East end of the wall.
Now pull down the
Points Menu again, and turn Off the add points option by again selecting it.
(or press the Escape key to turn it off)
Once both points
are in, we need to create a String showing the centreline of the proposed wall.
Pull down the
Strings Menu and select Add.
Enter an ID of
‘dam1’, and the default Folder of ‘lots’ will be adequate.
Don’t worry about Pen or Linetype at this
stage, and simply add in the string 600,601 for the proposed centreline.
Press the ‘Show’
button, and providing the string appears then press Finish.
Extracting Natural
Profiles and Sections
The next step in
the process is to extract a profile along this proposed centreline, and some
cross sections along it.
Use Strings,
Select Strings followed by Single String Selection to select the centreline
string you have just added.
Pull down the
Contour Menu; select Interpolate, followed by the Profiles and Sections option
to see the following screen.
Cross Sections at
20 metre intervals are sufficient for this exercise, but you should be aware
that the Xs on St and Xs on Crv fields allow you to specify whatever section
intervals you like, and you can have different intervals in straight and curved
sections of the alignment.
The fields Left
and Right allow you to determine how far on each side of the centreline (or
more correctly the alignment) the sections will extend.
In this case put
30 in each field.
Once you have
filled in all the fields, select the Refresh Table button, and the screen will
be updated to include all your chosen values.
Providing the screen appears to have
sensible values, you should select the Save button, and the screen will now
appear as seen below.
In the upper
window you will see the profile along your centreline.
In the smaller
middle window, you can see the first cross section, and if you wish, you can
use the Next and Previous buttons to move backwards and forwards through the
cross sections.
Providing you
screen is vaguely similar to the one shown above, select the OK+Save button.
Once the points
are stored with the string, you will see a message informing you of the fact –
press OK to be returned to the previous table.
Since we have no
further need of it at this time, select the Cancel button.
Now, select the
Display Profile Icon 
and you will see the Profile fill the
screen.
Next Select the
Display Section Icon 
to see the screen the section at Chainage 0
fill the screen.
Now pull down the Window Menu and select
Tile Roadworks to see the following screen.
If you wish to
see the sections, you can use the Next and Previous buttons, or the scroll bar to move through them.
The first thing
we need to do however is to enter the Vertical Design of where we would like
the dam wall to be.
We wish to
construct a dam wall with a height of 181 and allow 1.5 metres freeboard.
Enter the Design
Grading
To achieve this
it has been decided to construct a small spillway at RL 179.5 at the western
end of the wall.
Since we are going to work on the profile
design, Maximise your profile window, and then click your Right mouse button to
see the design options available.
The thing we need
to do here is to find a point that is at RL179.5 and is on the natural surface.
While you can
zoom up and move your cursor along the profile while watching the RL being
tracked in the window on the status bar, there is a more certain method that we
will use.
The first thing
we need to do is to create in a ‘temporary’ point at the correct RL of 179.5
somewhere near the western edge, or the start of the profile near Chainage 0.
Move the cursor
over as far to the left as it will go and then move up and down and watch as
the height approaches 179.5.
If you are steady
enough with the mouse you can press the left mouse button to add in a point
with an RL of 179.5. If not, just click anywhere near there to add in a point,
and then use the right button to bring up the Design Menu and select Design IP
Table.
Now type in
values of 0 and 179.5, and then select the OK button.
You will see a
small box signifying a Vertical IP appear on the profile, and this is the
‘temporary point’ we need..
Again press the
Right mouse button to bring up the Design Menu.
Choose the option
Add Grade to Natural, and when the program prompts for the IP, select the IP
you previously added. (You select it by positioning your cursor tip in the box
denoting the IP)
A window will pop
up requesting the grade to use, and since we wish to be level from the first IP
use a Grade of 0 and press OK.
You will now see
another IP appear on the profile, and this will be at RL 179.5.
Next we wish to
define the spillway, which is 3 metres wide and level, so use the Right mouse
button to bring up the options, and select Add by Grade.
You will be asked
to select the IP to Grade from, so ‘point to’ the IP on the profile, and then
enter a Grade of 0 for a Distance of 3 metres and select OK.
Again use the
Right mouse button and choose the Add by Grade option, and select the last IP
you added as the IP to grade from.
This time we wish
to batter up from the spillway to the top of the Dam Wall at a batter of 1:4,
or 25%. Since we need to go up 1.5
metres at 1:4, basic arithmetic tells us we need to go horizontally for 6
metres.
So, enter your Grade of 25 and a distance
of 6 and select OK to see another IP appear at what will be the top of our
wall.
Back to the Right
Button Menu and choose Add Grade to Natural.
Select the IP to
grade from and use a grade of 0 and select OK, and you will see another IP
appear on the profile at the right hand end.
All that remains
is to dispense with the “temporary IP” we used to get started, so bring up the
options with the Right Button, choose Delete, and point to the first IP.
The screen should
now be similar to that shown at left.
Now that the
Profile Grading or design is completed, select the Tile icon to ‘shrink’ the
profile window back to its normal size in the Roadworks view, and we will set
about designing a template to use to construct the wall.
Create a Design
‘Template’
In Ezicad terminology, a “template” is
simply the right hand side of what you would like the design cross section to be. If you are building a symmetrical structure,
you can then mirror that template on the left hand side, or you can use a
completely different one if you wish.
Since we will now
concentrate on Section Templates, maximise the Section window.
Now right click
in the window and you will see the Section Design Menu appear as seen at right
Choose Predefined
Templates and then choose a Bank Template
Tick the left and
right boxes to indicate you are constructing a ‘wall or bank’ that is
symmetrical about the centreline, and has this particular ‘template’ mirrored
about the centreline to achieve that.
The top of the
dam is to be 3 metres wide with a flat top – i.e. no cross fall on the top of
the wall. Fill in 1.5 for the width – remember that you are ‘designing the
right hand half, and half of 3 was 1.5 last time we looked.
Use 0 for the
grade.
You need a Cut
batter of 50% or 1:2 and a fill batter of 33.333, or 1:3.
Now Click the OK
button.
There will be no immediate change to the
section on display, but if you use the right arrow, or the Next button to move
to Chainage 40 your screen should appear as at right
Having
successfully designed the dam wall, we now need to know how much material it
will take to build it.
Calculate Volume Of Dam
Wall
Pull down the
Road menu, and select Volume.
Ordinarily, with
other jobs you might need to use the Design Volume Parameters to set up ranges
of chainages to calculate between and what road number to use etc.
However here our
chainages are greater then 0 and less than 1000, so everything falls within the
defaults and there is no need to make any changes.
If you wish to
look, you may do so, but there is no need to.
Instead, choose Design Volumes, and you will shortly see Word or WordPad
appear on your screen with a jumble of figures.
At this stage we
have been unable to crack the secret of how to convince Word or WordPad to go
into landscape mode automatically, and the information we have is too wide to
fit onto an A4 page in portrait mode.
Please pull down
the File menu in Word or WordPad, select Page Setup and choose Landscape mode
for the page.
You will find
that you should need some 28,500 cubic metres of material to build the wall.
If you wish to
print this out you may do so with the File print option in the Wordpad window,
and if you wish to save it, you can do so in whatever format you wish with the
File, Save As command.
Store Design Points To
Database
Now that we have
a wall designed, we need to store those design points into the database.
First you need to
create a Design Surface to store them on. Pull down the Contour Menu, select
Surface Parameters, and select the Add button.
Make it a Design surface, and Surface 2
will be added.
Now select OK to
close the parameter screen.
Pull down the
Road Menu, select Design Surface and choose the option Store Design Points.
The screen will
appear as at right.
Once you select
OK, the points will be stored into the database.
You are now
finished with the ‘Road’ side of things, so close down the Profile and Section
views.
The next step is
to check the design contours to see if they look reasonable, and if they do,
you then need to create a Combined Surface to use to calculate the storage
capacity of the dam you have just built.
Viewing the Design
Contours
Pull down the
Contour menu and form the model.
Then Calculate the Contours and Save them.
If you Zoom up
around the Dam Wall you should see a set of contours like those below.
If your contours
match those shown, all is well, but if they do not, you should backtrack
through this tutorial to find out what went wrong.
We now need to
construct a ‘combined surface’.
Forming Combined
Surface
Pull down the Contour Menu, select Surface
parameters, and select the Add button to add Surface 3 which you need to
specify as a Combined Surface.
Now pull down
Contour, select Merge Surfaces, and accept the default surfaces on offer.
Hit the OK
button.
The Combined
Model will be formed automatically and you should Calculate and Save the
Contours to achieve contours as seen at left
.
Calculate Storage
Capacity Of The Dam
Once the Combined
Surface is satisfactorily saved, you can use it to calculate the amount of
storage capacity in the reservoir or dam you have constructed.
Pull down
Contour, select Volume, and choose the Storage Capacity option.
Ignore the Start
Point for the moment as it only comes into play when you have more than one
closed contour where a capacity could be calculated.
Move down to the
Water Level field, and enter a value of 179.5.
In the Interval
field enter 0.5
The following
screen will soon appear, with the results presented in the now familiar Word or
Wordpad, and if you scroll down to the end of the file you will see the screen
shown below.
