NETWORK PROGRAMMING

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NETWORK PROGRAMMING

PTN=PROJECT NETWORK TECHNIQUE

TWO FAMILIESACTIVITY ON NODE EG and

ACTIVITY ON ARROW A.O.A

NETWORK PROGRAMMING

A DUMMY IS USED –IT IS ALWAYS SHOWN AS DOTTED LINE

Total FloatThe total amount by which an activity can be extended or

delayed without affecting the total project time (TPT)CalculationLatest Time Finish Event (LTFE) – Earliest Time Start

Event (ETSE) –Duration OrThe total amount by which an activity can be extended or

delayed without affecting succeeding (subsequent) activities or the Total Project Time.

NETWORK PROGRAMMING

2

NETWORK PROGRAMMINGEvery activity most be uniquely identified-

4

A

B

INCORRECT

Dummy activities and additional events will enable correct identification:

2

3

4

A=2-4B=3-4A

B

Dummy=2-3

A=2-4B=2-4

I J

NETWORK PROGRAMMING

Building up a network The time flow from left to right The start and end of each activity has an

event Activities are shown by arrows activity on

arrow networks Events are given numeric or ALFA

numeric number to identify

NETWORK PROGRAMMING

Head node numbers are higher than tail node numbers

Tail node is known as ‘I’ number Head nude is known as ‘j’ number Together they are shown as I J An event is a point where activities start or

end. All activities terminating at an event must be

completed before the next activity starts.

NETWORK PROGRAMMING

2 4

3

A=2-4B=2-3Dummy=3-4The dummy always have zero duration

I J

NO END DANGLES PERMITTEDNO LOOP PERMITTED

NOTE:

IF C AND D ARE BOTH DEPENDANTS ON A, AND D IS DEPENDANT ON B, ISNETWORK 1 CORRECT OR NETWORK 2 ?

NETWORK PROGRAMMINGNO END DANGLES PERMITTEDNO LOOP PERMITTED

NOTE:

IF C AND D ARE BOTH DEPENDANTS ON A, AND D IS DEPENDANT ON B, ISNETWORK 1 CORRECT OR NETWORK 2 ?

NETWORK 1A

B

C

D

Incorrect-because D id dependant on A and B,and C is dependant on A and B

NETWORK PROGRAMMING

2

2

A

B

C

D

zero duration

NETWORK 2

CORRECT DIAGRAM-A ZERO DURATION DUMMY IS INTRODUCEDThe start of D could be delayed for a specific time after the completion of A by putting a time duration on thedummy(ie a time transient dummy).

Note-there are 3 types of dummies:

1-Identical2-logical3-Transit

NETWORK PROGRAMMINGNetwork programming-Splitting work into section

Design a Network programming for an excavation, framework and concreting

One sectionExCAVATION FMWK CONCRETE

Two SectionsEXC. HALF FMWK HALF CONC HALF

EXC. HALF FMWK HALF CONC HALF

NETWORK PROGRAMMINGEXC. HALF FMWK HALF CONC HALF

EXC. HALF FMWK HALF CONC. HALF

Three Sections

START EXC. START FMWK START CONC.

CONTINUE EXC.CONTINUE FMWK CONTINUE CONC.

COMPLETE EXC. COMPLETE FMWKCOMPLETE CONC

NETWORK PROGRAMMINGNetwork Programming

The steps in producing a network are:

A) Listing the activitiesB) Producing a network showing the logical relationship

between activitiesc) Assessing the duration of each activitiesD) Determining the start and finish times of each

activities and the available floatE) Determining the resources requiredF) Produce the schedule

NETWORK PROGRAMMING

Ask yourself1) Which activity must be completed

before the next activity can start?2) Which activity can not start until this

activity is complete?3) Which activities have no logical

relationship with this activity and can not start at the same time?

NETWORK PROGRAMMING

Prepare a Network Diagram for the above project and reduce the duration of the project by at least 5 weeks.

NETWORK PROGRAMMING

2

7 0

Sequential Activities

Start

0 10 16 36 weeks

0 10 16 36

0 0

A -START A-CONTINUE A-FINISH

B -START B-CONTINUE B-FINISH

C -START C-CONTINUE C-FINISH

3 3 8 8

8 8 10 15

15 15 21 2128 28

3 5 2

2 2

6 7

21-2=19

21-6=15

GOING BACKWARD

GOING BACKWARD

15-0=15

GOING BACKWARD

NETWORK PROGRAMMING

Try this question- As a project manager you are asked to run a trench in three section prepare a networkdiagram to show total time, and a bar chart for the client.

MH-1 MH-2 MH-3

sewer

NETWORK PROGRAMMING

Start

Excavate section -1 Pipe bed section- 1 Lay pipe section-1 Back fill section- 1

Excavate section- 2 Pipe bed section- 2 Lay pipe section-2 Back fill section -2

Excavate section 3 Pipe bed section 3 Lay pipe section 3

3 1 1

Back fill section-3

3 1 1 2

4 6

NETWORK PROGRAMMING

20 30 40

50 60 70

80 90 100

110

2 2 3 5 4 6

55 76 7 8

88 99

10 10

3 1 1 2

3 1 1

2

12 12

2 2 2

0 1 1 1

0 0 0

0

NETWORK PROGRAMMING

ACTIVITY 1 2 3 4 5 6 7 8 9 10 11 12

10 20

20 50

50 80

20 30

50 60

80 90

30 40

60 70

90 100

40 70

70 100

100 110

float

float

float

float

float

float

1

3 4

6

5

7

2

du=12crash time(10)

du=10crash time(8)

du=13crash time(10)

du=8crash time(5)

du=15crash time(15)

du=10crash time(18)

du=11crash time(8)

1

3 4

6

5

33 3323 23

0 0

25 38

46 46

7

2

12 12

10 23

du=12crash time(10)

du=10crash time(8)

du=13crash time(10)

du=8crash time(5)

du=15crash time(15)

du=10crash time(18)

du=11crash time(8)

A

2

B

4

D2

C6

E4

F6

G8

K

10

H

5

P

8

J3

L1

N

M3

Q

7

S

U

1

T6

V

7W

3

X

10

AA

5

BB

Y

7

CC9

EE4

FF

12

GG14

HH

6

JJ

7

R5

DD

Z

1 2

12

14 17 19

13

15

16

18

3

5

4 9

6

11

7

10

21 22

20

S

8

DU=2

DU=4

DU=2

DU=6DU=8 DU=10

DU=3

DU=5

DU=1

DU=7DU=8DU=6

DU=9DU=7

DU=1

DU=5

DU=

DU=4

DU=6

DU=14

DU=12DU=10

A

B

D

F

G

K

C P Q

DU=6

DU=8

DU=3

DU=7

DU=5

UT

V

W

Y

H

L

CC

HH

EE

AA

FFX

GG

0 0

2 2

8 8

6 21

8 2914 35

DU=4E

19 42

19 43

16 16 26 26

26 48

38 38

DD

BB

22 43

32 5319 52

12 38J

20 46

32 53

R M

65 65

58 5826 49

52 52