P1: OSO
JWDD004-EP JWDD004-Halpin-v7 August 24, 2005 18:5
CHAPTER 4 Four Types of Fee Structure
1. Cost + Percent of Cost
2. Cost + Fixed Fee
3. Cost + Fixed Fee + Profit Sharing
4. Cost + Sliding fee, Sliding Fee = R(2T - A)
where T = target price, R = base price value, A = actual cost of construction
CHAPTER 7 Forward Pass Equations
EFT(I ) = EST(I ) + DUR(I )
all I
EST(J) = max [EFT(I )]
I¡ÊM
where I is a member of the set of M activities that precede activity J.
Backward Pass Equations
LST(J) = LFT(J) - DUR(J)
all J
LFT(I ) = min [LST(J)]
J¡ÊM
where J is a member of the set of M activities that follow activity I.
Four Types of Activity Float
Total Float
TF(I) = LFT(I) - [EST(I) + DUR(I)]
= LFT(I) - EFT(I)
Where I is a member of the set of
preceding activities.
Free Float
FF(I) = min [EST(J)] - EFT(I)
Where J is a member of the set of
follower activities.
Interfering Float
IF(I) = TF(I) - FF(I)
Independent Float
Ind. F = min[EST(J)] - LFT(I)
EST(I) EFT(I) LFT(I)
DUR(I) TF
EST(I) EFT(I)
min[EST(J)]
J M
DUR(I) FF
LFT(I) EFT(I)
TF
IF
DUR(I)
LST(I) LFT(I) EST(I) min[EST(J)]
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CHAPTER 8 PERT Equations
Expected duration te =
(ta + 4tm + tb)
6
where ta is the most optimistic duration estimate, tm is the most likely duration estimate,
and tb is the most pessimistic duration estimate.
Variance for each PERT activity £m2 = (tb - ta)
6 2
Z =
Mean - x
ÃVariance
or Z =
( øX
- x)
£m
where £m is the standard deviation of the cumulative normal distribution.
CHAPTER 9
Pay = 1.25(indirect expense + direct expense)
-0.10[1.25(indirect expense + direct expense)]
Rate of Return
PW[REV (I )] -
PW[EXP(I )] = 0
where REV(I ) = revenue for period I
EXP(I ) = expenditure for period I
PW = present worth of these values
CHAPTER 11
Depreciation Cost per Hour =
Purchase Price - Tire Value
Estimated Service Life in Hours
Average Annual Value (AAV) =
C(n + 1)
2n
,
where AAV is the average annual value, C is the initial new value of the asset, and n is the
number of service life years.
Average Annual Value (AAV), including the salvage value =
C(n + 1) + S(n - 1)
The hourly charge for IIT is calculated as:
IIT/hour =
factor ¡Ñ delivery price
1000
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CHAPTER 12 Power Required = RR ± GR
Percent swell = 1
load factor- 1 ¡Ñ 100
where Load factor =
pounds per cubic yard-loose
pounds per cubic yard-bank
Grade Resistance (GR) = percent grade ¡Ñ 20 lb/ton/% grade ¡Ñ weight on wheels (tons)
Equivalent percent grade =
RR
20 lb/ton/% grade
Usable pounds pull = (coefficient of traction) ¡Ñ (weight on drivers)
CHAPTER 13
Resource-hours per hour
Units per hour = RH/unit, where RH = resource hour
The basic equation for unit pricing:
Resource cost per unit time
Production rate =
$/hr
unit/hr = $/unit
CHAPTER 15 The five parameters which form the foundation of the ÒearnedÓ value concept are:
Budgeted Cost of Work Schedule (BCWS) = Value of the baseline at a given time
Actual Cost of Worked Performed (ACWP) - Measured in the field
Budgeted Cost of Worked Performed (BCWP) = [% Complete] ¡Ñ BCAC
Budgeted Cost At Completion (BCAC) = Estimated Total Cost for the work Package
Actual Quantity of Worked Performed (AQWP) - Measured in the field
CV, Cost Variance = BCWP - ACWP
SV, Schedule Variance = BCWP - BCWS
CPI, Cost Performance Index = BCWP/ACWP
CPI <1.0 indicates cost overrun of budget
CPI >1.0 indicates actual cost less than budgeted cost
SPI, Schedule Performance Index = BCWP/BCWS
Pc =
Ps
(100 - Ps )
where Pc = percentage applied to the projectÕs total direct cost for the coming year
Ps = percentage of total volume in the reference year incurred as fixed or G&A
expense
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Januszek66