# Project Control: Developing the As-Planned S-Curves

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```					Project Control: Developing
the As-Planned S-Curves
Part #2
March 3, 2012
Hide/Unhide Exercises
Purpose
Illustrate how to develop a set of As-
Planned S-Curves from scheduling
information and estimates developed
sometime before actual construction
operations begin.
Review the conceptual design estimating
process to the extent necessary to set the
context.
Learning Objectives
Be able to construct an as-planned schedule
of work and cost versus elapsed time from a
typical (but simplified) construction project
Gantt Chart.

Be able to plot and identify the as Planned S-
Curves best representing these schedules.
Who Develops the As Planned
Gantt Chart? And When?
It depends upon what part of the process is
in question.
We are going to assume that the Gantt Chart
is developed by the Contractor to plan
construction operations.
We are going to assume that the schedule
data are generated sometime before the
onset of actual field operations.
Example Construction Project
The project is to reconstruct 2-miles of park
standards. This involves the following tasks:
1. Mobilization – Equipment, office set up, etc.
2. Sub-base preparation – hauling, grading and
compaction, redo of some culverts, etc.
3. Base course construction – hauling, grading and
compaction.
4. Wearing Course construction – shoot and chip
5. Demobilization – Clean up, equipment, office,
etc.
Class Discussion Exercise #2.1
on Construction Methods.
following:
What is Base Material and what is its purpose
in the design of the road?
How is the Base built?
What is “shoot and chip?”
What is Pea Gravel?
What is the design profile of a FM Road?
Cost Data
1 Mobilization           1         1,000
2 Sub Base               10        3,500
3 Base                   11       51,000
4 Pave                   4        25,000
5 Demobilization         2         1,000
Assume:
All labor, material and equipment cost estimates are
available from the estimating process.
Maximum Task overlap with a 1-day minimum delay on
an early start schedule.
Assumed Estimating Process
The entire project is broken into Work Packages (work
breakdown structure): build base, shoot and chip, etc.
Estimated unit quantities for each work package are calculated
from the plans and specifications at an appropriate level of
detail.
The corresponding unit prices and productivity rates are
obtained from historical data – We will use the R. S. Means
manual in this class.
Work Package (or Task or Activity) durations and costs are
derived from the historical data as applied to the estimates.
These data serve as inputs to the scheduling process which
result in Bar-Charts similar to the one on the next slide.
Class Exercise 2.2
As individuals describe the crew
(equipment and personnel) configuration
necessary to construct the base course.
As Pairs agree upon the configuration.
As a Team, estimate the hourly cost rate.
Example Gantt Chart with
Related S-Curve % Data
Task          Days    \$\$/Day      ES           1        2       3        4        5        6        7        8        9       10 11 12 13 14 15 16 17
M              1    \$ 1,000       1           M
S             10    \$ 4,000       2                   S       S        S        S        S        S        S        S        S        S
B             11    \$ 50,000      3                           B        B        B        B        B        B        B        B        B        B        B
S              4    \$ 25,000     12                                                                                                            S        S        S        S
D              2    \$ 1,000      16                                                                                                                                                D       D

693,000
54,000
54,000
54,000
54,000
54,000
54,000
54,000
54,000
54,000
75,000
75,000
25,000
25,000
Cost in \$\$'s
1,000
4,000

1,000
1,000
Cumulative
Daily Cost

100%

100%

100%
100%
16%

24%

32%

40%

47%

55%

63%

71%

82%

92%

96%
0%

1%

9%
e Work Units
Cummulativ
Daily Work

28
1
1
2
2
2
2
2
2
2
2
2
2
2
1
1
1
1
100%
100%
14%

21%

29%

36%

43%

50%

57%

64%

71%

79%

86%

89%

93%

96%
4%

7%

Simplifying assumptions: All work is equally weighted where 1 day equals 1 unit of
work. Daily work accomplished is NOT a function of daily cost.
Class Exercise #2.3
As Individuals, compute the number of
cubic yards of base material required to
build 2-miles of FM Road base, 24-feet
wide, and 1-foot thick?
As Pairs, compare answers and then
compute the linear feet of daily
progress, if you can build 2,700 sq-yds
of base per day?
What Does all                Day   Cost % Work %

this Imply?                   1
2
0%
1%
4%
7%
3      9%    14%
The relationship between      4     16%    21%
time and cost and time        5
6
24%
32%
29%
36%
and work.                     7     40%    43%
8     47%    50%
9     55%    57%
For example, at the end of   10     63%    64%
day 8 you plan to have       11
12
71%
82%
71%
79%
completed 50% of the         13     92%    86%
Work and to have spent       14     96%    89%
15     100%   93%
47% of the Budget.           16     100%   96%
17     100%   100%
Corresponding As-Planned S-
Curves
As Planned S-Curves
100%                                                    200%
Note: The                          90%                                                     180%
relationship                       80%                                                     160%

between the
Cummulative Cost
70%                                                     140%

Cumulative Work
scales. There                      60%                                                     120%

is a reason –                      50%                                                     100%

to make                            40%                                                     80%

room for the
30%                                                     60%

20%                                                     40%
As-Built                           10%                                                     20%
S-Curves                           0%                                                     0%
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
Schedule in Days
Exercise #2.4             Day
1
Cost % Work %
0%     4%
2      1%     7%
3      9%    14%
4     16%    21%
Individually, using      5     24%    29%
engineering paper,       6     32%    36%
plot the S-Curves for    7     40%    43%
8     47%    50%
these data, label the    9     55%    57%
axes, the curves, and   10     63%    64%
the plot.               11     71%    71%
12     82%    79%
Turn in your work       13     92%    86%
before you leave.       14     96%    89%
15     100%   93%
16     100%   96%
17     100%   100%
Module Assessment Question