Planning & Control
Activity on the Arrow Networks
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Tutorial 3:
Activity on the Arrow Networks
In this tutorial, you will gain experience of developing activity-on-the-arrow networks, and
inputting simple projects to P3.
Question 3.1: Neatly sketch the activity-on-the-arrow network for the following logical activity
constraints (add to your submission):
Activities B and C both follow activity A
Activity D follows activity B
Activity E follows activity C
Activities D and E precede activity F
Question 3.2: Input the above activity-on-the-arrow network into P3 with arbitrary 1 day durations
for the activities (print out and add to your submission).
Question 3.3: Neatly sketch an activity-on-the-arrow network for the following logical activity
constraints (add to your submission):
Activity B follows activity A
Activities C and D both follow activity B
Activity H follows activity D only
Activities E and I both follow activity C
Activity F follows activity E
Activity J follows activities I and H
Activity G follows activity F
Activity K follows activity J
Activity L follows both activities K and G
Question 3.4: Input the above activity on the arrow network into P3 with arbitrary 2 day durations
for the activities (print out and add to your submission).
Question 3.5: Neatly sketch an activity-on-the-arrow network for the following logical activity
constraints (add to your submission):
Activities G and H both follow activity F
Activity D follows both activities B and C
Activity C precedes both activities F and D
Activity J follows activity E only and precedes activity L
Activity K follows activity D and precedes activity L
Activity L follows both activities J and K and merges with activities M and N at the
objective event (the end event)
Activity M follows activity G
Activity A commences the network
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Activity on the Arrow Networks
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Activity N follows activity H
Activities B and C follow activity A
Activity E follows activity B and precedes activity J
Activity F follows activity C and precedes activities G and H
Question 3.6: Input the above activity-on-the-arrow network into P3 with arbitrary 5 day durations
for the activities (print out and add to your submission).
Question 3.7: A bus shelter is to be constructed at the entrance to a large housing development. It
consists of a stopping area for buses and a small shelter approximately 8’ x 16’ in plan area (see
Figure T3.1). The floor is a concrete slab and the walls are brick. There is a timber beam across
the front of the shelter that supports a laminated timber roof. The shelter is illuminated by two
light fixtures, one on each end wall. The existing sidewalk is illuminated by two light fixtures, one
on each end wall. The existing curb and sidewalk are to be removed and replaced as shown in the
figure to provide stopping space for buses away from the traffic lane. The stopping space will need
to be paved. The project has been broken down into a number of activities with estimates of their
duration. These activities, in no particular order, are:
Shelter slab: Includes the fine grading, casting of concrete, and finishing. Duration = 2
days.
Shelter walls: Includes the laying of the brick for the walls and the inclusion of the
electrical conduit for the lighting. Duration = 3 days.
Shelter roof: Includes the construction of the laminated roof, the covering with a built-up
roofing, and the trimming of the edges. Duration = 2 days.
Roof beam: Includes the cutting and erection of the beam. Duration = 1 day.
Cut curb: Includes the cutting of the existing curb and breaking up of the existing curb
and sidewalk. Duration = 1 day.
Excavation: Includes the removal of broken concrete curb and sidewalk, the excavation of
the parking space, the excavation of the space for the shelter slab and sidewalk. Duration =
2 days.
Curb and gutter: Includes the forming, casting, and finishing of the new curb and gutter.
Duration = 2 days.
Sidewalk: Includes forming, casting and finishing of the new sidewalk. Duration = 2
days.
Shelter seat: Includes the attachment of seat brackets to the wall and the construction of
the seat. Duration = 1 day.
Lights: Includes the wiring and attachment of the light fixtures. Duration = 1 day.
Paint: Includes putting a stained exterior finish on the edges of the roof, roof beam, and
the shelter seat. Duration = 1 day.
Paving: Includes the laying of the finished paving in the parking strip. Duration = 1 day.
Neatly sketch an activity-on-the-arrow network for the above bus shelter project. Your network
should make as many activities concurrent (parallel) as possible but without violating any logical
constraints (for example, the shelter slab must be built before the shelter walls) or space constraints
(the shelter roof cannot be constructed at the same time as the shelter seat as they need access to
the same space) (add to your submission).
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Activity on the Arrow Networks
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Question 3.8: Input the above bus shelter project into P3 with a project starting date of October
1st of this year (print out and add to your submission).
A
Plan
5m
Line of Roof
3m
Not To
Scale
Light fixture
2m
2m
A
Section A-A
Figure T3.1: Bus Shelter Construction Project.
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Question 3.9: Input to P3 the Work Breakdown Structure (WBS) shown in Figure T3.2 below, in
accordance with the following instructions:
1. Power-up P3.
2. Open a new project file.
3. Select DATA  WBS…, and from the WBS Dictionary window select the Structure…
button.
4. In the WBS (Work Breakdown Structure) window type in 5 for the Width of each of the
first 5 levels, type in a period (.) for the Separator for each of the first 4 levels, and select
OK. This allows you to build a WBS with up to 5 levels of break down, and with input
codes of up to 5 characters per level, separated by periods (example codes may be: 1.1.2.1.3
or 7.2.4.1.2).
5. Input to P3 the work breakdown shown in Figure T3.2, using the WBS window, as follows:
 In the WBS window, select the + button (near the Code field) and type in the following
to the Code and Title fields respectively, then select the check mark (note, put the first
code, 1, as far to the left of the Code field as possible):
1

.
.
.
Office Facility
In the WBS window, select the + button again, and type in the following to the Code
and Title fields respectively, then select the check mark (again, make sure each code is
input as far to the left of its section of the box as possible):
1

.
.1
.
.
.
Site work
Continue with the above process to build the entire work breakdown described by
Figure T3.2. The next 7 Codes and Titles would be as follows
1
1
1
1
1
1
1
.1
.1
.1
.2
.2
.2
.2
.1
.2
.3
.
.1
.1
.1
.
.
.
.
.
.1
.2
.
.
.
.
Preliminary site work
U/G Utilities
Landscaping
Building
Structural system
Foundation
Steel Frame
.
.
etc…
Now select OK.
6. Switch on the WBS as follows:
 Select Format  Organize…, select the Work breakdown radio button, check the
Display empty workbreakdown levels switch. This will ensure that the WBS is
visible even for activity groups that do not yet contain activities.
 Under the Total column, make sure that all fields say None. If a field says anything
else (if the second row says Top, for example), then change it to None.
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
Select Organize Now. Look at the WBS and note the nesting layout of the activity
groups (with Office Facility at the outer level).
7. Select Format  Organize…, select the Options… button, and select the As bands radio
button and (under the Activity Columns region) check both Value and Description. Select
OK and Organize Now. Note the bands now reach across the page and both the level
Code and Title appear on the bands.
8. Click on the group Office Facility and input an activity of 10 days duration with an
Activity ID of your choice and the Activity Description ‘Mobilize’.
9. Click on the subgroup Preliminary sitework, and input 2 activities ‘clear and grub’ and
‘rough grade’, with 5 days duration each.
10. Click on the subgroup Foundation and input 2 activities ‘layout’ and ‘excavate’ of 4 days
each. Note, in a real project, there would be many activities (at least in each of the lowest
level groups), but for this exercise the above 5 activities will suffice.
11. Link the activities according to their logical constraints and schedule the project.
12. Note, each second level group in the WBS has a summary bar representing the combined
duration for the activities in its group. This can be switched off as follows:
 Select Format  Organize…, and under the Total column on the second row change
Top to None, then select Organize Now.
13. Select Format  Bars…, check Weekends, check Weekends, and select Close. Note,
the bars now show necking for periods of inactivity (weekends).
(Print out and add to your submission).
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Office Facility:
Site work:
Box 1
Box 1.1
Preliminary site work:
Box 1.1.1
U/G Utilities:
Box 1.1.2
Landscaping:
Box 1.1.3
Building:
Structural System:
Box 1.2
Box 1.2.1
Foundation:
Box 1.2.1.1
Steel Frame:
Box 1.2.1.2
RC Stairwell:
Box 1.2.1.3
Exterior:
Box 1.2.2
CMU & Brick Veneer:
Box 1.2.2.1
Doors & Windows:
Box 1.2.2.2
Roof:
Box 1.2.2.3
Interior:
1st Floor:
Box 1.2.3
Box 1.2.3.1
Mechanical
Box 1.2.3.1.1
Electrical
Box 1.2.3.1.2
Plumbing
Box 1.2.3.1.3
Walls & Ceilings
2nd Floor:
Box 1.2.3.1.4
Box 1.2.3.2
Mechanical
Box 1.2.3.2.1
Electrical
Box 1.2.3.2.2
Plumbing
Walls & Ceilings
3rd Floor:
Box 1.2.3.2.4
Box 1.2.3.3
Box 1.2.3.3.1
Electrical
Box 1.2.3.3.2
Walls & Ceilings
Break Down of an Office Facility in the
Form of a Box Classification
.
Box 1.2.3.2.3
Mechanical
Plumbing
Figure T3.2: Component-Oriented
Box 1.2.3.3.3
Box 1.2.3.3.4
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