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A T H E 8 I 8
S U B M I T T E D TO THE D E P A R T ME NT OF MANAGEMENT AND THE I N S T I T U T E OF MANAGEMENT S C I E N C E S
OF B I L K E N T U N I V E R S I T Y
I N P A R T I A L F U L F I L L M E N T OF THE R E Q U I R E M E N T S
f o r t h e d e g r e e OF
MA S T E R OF B U S I N E S S A D M I N I S T R A T I O N
By
Oguz Aba PEKER February, 1989
но
¿f HSé P I Ѣ "î;vv
I c e r t ify th a t I have read this th esis and that in rny opinion it is fully adequate, in scope and in quality, as a thesis fo r the degree o f the Master o f Bus fries s Administration.
Assist. Prof. Erdal Erel
I c e r t ify that I have read this th esis and that in my opinion i t is fu lly adequate, in scope and in quality, as a thesis fo r the degree o f the Master o f Business Administration.
A ssist. Prof. Dilek Yeldan
I c e r t ify that I have read this th esis and that in my opinion i t is fu lly adequate, in scope and in quality, as a thesis fo r the degree o f the Master o f Business Administration.
r
/ /
Assist. Prof.'C an Birnga
Approved fo r the In stitu te o f Management Sciences.
Prof. Dr. Siibidey Togan
ÖZET
MODEL İÇMESÜYÜ ARITMA TESISİMIM
PLANLAMA VE ZAMAN ÇİZELGESİNİN HAZIRLANMASINDA KRİTİK YOL METODU NUN KULLANIMI
OÖUZ ATA PEKER
Y ü k s e k L i s a n s T e z i , i ş l e t m e B ilim le r E n s t i t ü s ü T e z Y ö n e t i c i s i : Y. D oc. Dr. ERDAL EREL
Ş u b a t 1 9 8 9 , 1 0 2 S a y f a
Kritik Yol Metodu (KYM) p rojelerin planlanmasında ve zaman çizelgesinin hazırlanmasında yön eticilere yardım cı, d eğerli ve güçlü bir a r a ç tır . Bu çalışmada, KYM bü5’'ük bir içmesuyu arıtm a tesisin e uygulandı. Bu projenin zaman ç iz e lg e s i KYM ile hesaplandı ve bunun ilişki ağı ve çubuk diyagramı, proje yönetim ve k on trol programı olan Primavera P r o je ct Planner ile ç iz ild i
Anahtar Kelimeler: kritik y o l metodu , planlama ve saman ç iz e lg e s i ,
içmesuyu arıtma t e s i s i
ACKNOWLEDGMENTS
The author should like to express his thanks to Assist. Prof. Erdal Erel fo r his .supervision and criticism s o f the text, and A ssist. Prof. DUek Yeldan and A ssist. Prof. Can Simga fo r their helpful suggestions.
The author also wishes to thank warmly Ids d ire cto r o f Mr. Ugur S r r c a li and his friends in liis o ffic e a t DSi fo r th eir valuable supports.
The author would like to aclmowledge with gratitude the endless
supports he has received from his wife, Hande Peker and famils-'
throughout the study.
CONTENTS
1 INTRODUCTION ... 1
1.1 HISTORY OF WATER TREATMENT ... 1
1.2 OBJECTIVES OF WATER TREATMENT ... 2
1..3 DRINKING WATER. TREATMENT ... 4
1.4 PROJECT MANAGEMENT ... 6
1.5 DEVELOPMENT OF THE NETWORK PLAN CONCEPT ... 9
1.6 AREAS OF APPLICATION ... 14
1.7 CRITICAL PATH METHOD AND ITS ADVANTAGES ... 15
1.8 PURPOSE OF THE THESIS ... 18
1.9 OUTLINE OF THE THESIS ... 19
2 APPLYING CPM TO A DRINKING WATER TREATMENT PLANT PROJECT ... 2 1 2.1 DEFINITIONS ... 21
2.2 PROJECT CALENDAR ... 2.3 2.3 SPECIFYING THE PROJECT ACTIVITIES AND THEIR. ESTIMATED DURATIONS ... 23
2.4 SCHEDULE PRESENTATION ... 25
2.5 CRITICAL PATH IDENTIFICATION ... 26
3 DISCUSSION ... 2 8 4 CONCLUSION AND RECOMMENDATIONS ... 3 2 REFERENCES ... 3 4 APPENDICES ... 3 7 APPENDIX A:PRESENTATION OF THE PRIMAVERA ... 38
APPENDIX B:SCHEDULE REPORTS ... 41
APPENDIX B DPROJECT SCHEDULE SORTED BY EARLY START & TOTAL FLOAT ... 42
APPENDIX B 2:PROJECT SCHEDULE WITH PREDECESSORS AND SUCCESSORS ... 46
APPENDIX B 3:PROJECT SCHEDULE WITH DETAILED PREDECESSORS AND SUCCESSORS ... 58
APPENDIX C;BAR CHARTS ... 68
APPENDIX C 1;WEEKLY BAR CHART WITH ONE BAR ... 69
APPENDIX C 2:WEEKLY BAR CHART WITH TWO BARS ... 82
APPENDIX D;NETWORK LOGIC DIAGRAMS ... 95
APPENDIX D 1:NETWORK LOGIC DIAGRAM FOR. CRITICAL PATH ... 96
APPENDIX D 2:TIME-SCALED NETWORK LOGIC DIAGRAM ... 98
VITA ... 101
INDEX ... 102
LIST OF FIGURES
FIGURE 1 - The R epresentation o f Arrow and Precedence Diagrams 13
LIST OF TABLES
TABLE 1 - Costs and Savings 18
INTRODUCTION
1 . 1 H ISTO RY OF WATER TREATMENT
Evidence o f man's desire to improve the quality o f water is found in the e a r lie s t recordings o f knowledge. This is illu stra te d by a quotation from a body o f medical lore in Sanskrit said to date from 2000 B.C. : "Impure water should be purified by being boiled ov er a
fir e , o r being heated in the sun, o r by dipping a heated iron into it,
o r i t may be purified by filtr a t io n through sand and co a rse gra vel and then allowed to cool'.H I Throughout liistory, examples are seen o f man's e f f o r t s to t r e a t water; some o f the early treatm ent plants bear a surprising resemblance to those hi use today. In 1304 the f i r s t known f i l t e r to serve an en tire c ity was completed a t Paisley, Scotland.tis ] The p u rifica tion plants which were built in the early nineteenth century, became the forerunner fo r s u c c e s s fu l plants which were built h'l the late nhieteenth century and in the early tw entieth century. Later, the f i r s t municipal application o f chlorine a.s a water d isin fecta n t was seen. The period with the beginning o f a dramatic decline in the death ra te from typhoid fev er, was described as the "era o f g rea t sanitary awakenhig".[i]
The existing water treatm ent knowledge expanded with the beginning o f 1913. In the foUowhig se ctio n s, the o b je ctiv e s o f water treatment and some p ro ce sse s which are used in the water treatment, are explained.
The three basic o b je ctiv e s o f water treatment are :
1. Production o f water that is s a fe fo r human consumption 2. Production o f water that is appealing to the consumer
3. Production o f water using fa c ilitie s reasonable with r e s p e c t to
ca p ita l and operating costs.
In the design o f water treatm ent plants, the provision o f sa fe water is the prime goal; anything less is unacceptable. A properly designed plant is not a guarantee o f sa fe ty , however. Skillful and a le r t plant operation and a tten tion to the sanitary requirements o f the sou rce o f supply and distribu tion system are equally important.
Water treatm ent plants have demonstrated the ability to produce
s a fe T-7a te r under adverse conditions. Outbreaks o f waterborne
disease.s involving public water supplies are now extremely rare. Most
o f the outbreaks that have occu rred in recen t years have been
caused by the contamination o f untreated supplies, stora g e tanks, and distribu tion system s. There have been occa sion a l outbreaks caused by inadequate c o n tr o l o f treatment fa c ilitie s . These serve as reminders o f the need fo r uninterrupted treatm ent and unceasing a tten tion to operating details. Because o f the already low incidence o f waterborne d isea ses, new plants unlike those built decades ea rlier, will not produce a sp ecta cu la r lowering o f disease rates. However, their task in furnishing a s a fe water will, in many instances, be more d iffic u lt because they will be treatin g a water o f poorer quality.
The second basic o b je ctiv e o f water treatm ent is the production o f
1.2 OBJECTIVES OF WATER TREATMENT
water appealing to the consumer. Ideally, an appealing water is one th at is cle a r and c o lo r le s s , pleasant to the ta ste , and cooL It is
nonstaining, and i t is neitlier c o rro s iv e nor sca le forming. In
sa tis fy in g the demand fo r an appealing water, the treatm ent plant
must be able to cope with variations in flow and raw water quality to produce a water o f uniformly good quality. An additional reason fo r production o f an appealing water is to discourage the consumer from turnlTig to some other, unsafe sou rce o f water.
The consumer is principally'' in te re ste d in the quality o f water delivered to the tap in h is/her home or place o f business, as opposed
to the quality a t the treatm ent plant. Therefore, water u tility
operations should be such that the quality is not Impaired as water flows from the treatm ent plant through the distribu tion system to the consumer. Treatment plant design and operation should seek to provide a sta b le water and to prevent growths in the distribu tion system.
The third basic o b je ctiv e is th at water treatment should be
accomplished using fa c ilitie s that .are reasonable with r e s p e c t to
ca p ita l and operating c o sts. This does not mean that a plant's
capability to meet emergency situ ation s or ju stifia b le future
conditions should be sacrificed, fo r the sake o f in itia l savings. It
does mean that, in plant design, the various altern atives should be investigated, includirig the making o f performance and c o s t studies,
and that an optimum design be evolved based on sound engineering
principles and also with fu ll consideration o f the a b ilities o f
opei’ating and maintenance p erson n ellil
The Dririkirig Water Treatment Plant c o n sists o f the following p ro ce sse s :
Aeration : Aeration is used fo r removing e x ce s s ’ gases such as hydrogen sulpMde, oxygen, carbon dioxide, in case o f sh o rt o f oxygen to oxidise the ferrou s and manganous ions, to n itrify the ammonia under the certa in conditions and to increase the oxygen content and thus to make the water more potable.[3]
Coagulation : Coagulation is defined as the process by which
co llo id a l p a rticles are destabilised, and is achieved mainly by
neutralising th eir e le c t r ic charge. The product used fo r this
n eutralisation is called a coagulant.
F locculation : Flocculation is the massing tog eth er o f discharged p a rticles as they are brought into co n ta ct with one another by stirring. Tliis leads to the form ation o f flo e s, wMch can be s e tt le d o r filte r e d ou t a t a la te r sta ge o f treatment. Certain products, called floccu la tin g agents, may promote the formation o f flo cs.[3 ]
Sedimentation : Sedimentation following chemical coagulation and
flo ccu la tio n is used to remove se ttle a b le solids suspended in
water.[3] F locculation and sedimentation are not distinctlj'' separate treatm ents because there can be fu rth er flo ccu la tio n in the s e ttlin g tank th at is sometimes called as a c la r ifie r as well
F iltra tion : F iltra tion is a p rocess that con sists o f passing a solid -liq u id mixture through a porous m aterial (filte r ) wMch retains the solids and allows the liquid (filtr a te ) to pass throughts]
1.3 DRINKING WATER TREATMENT
Chlorination and D isinfection : In order to achieve o b je c tiv e s such
as the removal o f certa in undesirable inorganic substances In
solu tion (e.g. iron o r manganese compounds) that is called chlorjnatlon, the elimination o f foreign ta s te s and smells and the d estru ction o f pathogenic microorganisms that is called disinfection, water treatment usually makes use o f cMorine iri both casesJ ^ ]
pH Adjustments : Usually su lfu ric acid ( H2SO4 ) and lime ( Ca(0H)2 )
are used in water treatment to adju st the pH le v e l pH values indicate whether the water is acid or aüîallne. They have no health significance, but rep resen t a very important fa c to r in determining the aggressive a ction o f the water. Moreover, the pH plajcs an important role in the e ffic ie n c y o f the coagulation process.
The Dz'inklm Hater Treatment Plant is where the s e t o f n ecessa ry p rocesses as mentioned above takes place, in order to obtain a sta b le drinking water th at is sa fe fo r human consumption, pleasant to ta s te , nonstaining and neither c o rr o s iv e nor scale forming.
In Turkej'', generally su rfa ce water is used fo r drinking water
treatment. The ca p a cities o f these plants vary from 5,000 to
1.128.000 m3/day. The small capacity plants are usually compact plants th at serv e some villages o r c it ie s with a population o f less than
100.000 people. The high capacity plants are large con stru ction
p ro je c ts th at are comprised o f a unique s e t o f a c tiv itie s established to realise a given s e t o f o b je c tiv e s in a limited life span. Usually, these large p ro je c ts c o n s is t o f some o f the foUowiiig main operation units :
l.Raw water in let and aeration unit.
2. Flash mixers, 3. C larifiers, 4. F ilters,
5. Treated water tanks, 6. Wash water holding tanks, 7. Thickeners and sludge station, 8. C he mic a 1 bu ilding.
This th esis fo cu se s on a large driiiking water treatm ent p la n t p r o je c t that has a capacity o f 250,000 m3/day, and serv es approximately 650,000 people. The large driniting water treatment plant requires a
con stru ction p rocess but the mobile compact plant requires a
manufacture p rocess. These con stru ction p ro je cts are comprised o f a unique and large s e t o f a c tiv itie s and th eir in stalla tion p rocesses are more complex than the mobile compact plants. Therefore, these con stru ction p ro je cts require incentive planning and scheduling which are necessary to complete them on the estim ated time.
These incentive planning and scheduling are involved hi p r o je c t
management In the next section , p ro je c t management and the
resp on sib ilities o f a p r o je c t manager are explahied.
1 . 4 PROJECT MANAGEMENT
In order to understand p r o je c t management, one must beghi with the d efin ition o f a p roject. A p ro je c t can be considered to be s e r ie s o f a c tiv it ie s and tasks th at :
Lhave a s p e c ific o b je ctiv e to be completed within certa h i
s pe c i f ica t io ns
2. have defined s t a r t and end dates 3. have funding limits (if applicable)
4. consume resou rces (ie . , money, people, equipment)
P r o je ct management irwolves p r o je c t plannirig and p r o je c t monitoring. They are in the following :
1. P ro je ct planning
a. Definition o f work requirements b. Definition o f quantity o f work c. Definition o f resou rces needed 2. P ro je ct monitoring
a. Tracking progress
b. Comparing a ctu a l to predicted c. Analysing iiopact
d. Makirig adjustment.
S u cce ssfu l p r o je c t management can then be defined as having
achieved the p r o je c t o b je c tiv e s : 1. within time
2. within c o s t
•3.at the desired perform ance/technology le v e l
4.while utilising the assigned resou rces e ffe c t iv e ly and e ffic ie n tly . P oten tia l ben efits from p r o je c t management are :
1 id en tifica tion o f function resp on sib ilities to ensure that a ll
a c tiv it ie s are accounted for, regardless o f personnel turnover 2.minimising the need fo r continuous reporting
3.id en tifica tion o f time limits fo r scheduling
4.id en tifica tion o f a methodology fo r t r a d e - o f f analysis
5. measure merit o f accomplishment against plans
e.earlj'·' id en tifica tion o f problems so that c o r r e c tiv e action may follow
7.improved estim ating capability fo r future planning
8.knowing when o b je ctiv e s can not be met or will be exceeded
P r o je ct manager is responsible fo r coordinatiiig and bitegrating a c tiv itie s a cross multiple, fu nctional lines. In order to achieve this, a p r o je c t manager needs stron g communicative and interpersonal skills.
He/she must become familiar with the operations o f each line
organisation, and should have a general knowledge o f the teclm ology (unless he o r she is managirig R&D a ctiv itie s,iri which case a command o f technology is more important than a general understanding).
The major respon sib ility o f the p r o je c t manager is planning. If p r o je c t planning is performed c o rr e ctly , then it is conceivable that the p r o je c t manager will work himself or h e rse lf out o f a jo b because the p r o je c t can run by its e lf. This rarely happens however. Few p ro je c ts are ev er completed without c o n flic ts or t r a d e -o ffs fo r the p r o je c t manager to resolve,
With the help o f PERT (Program Evaluation and Review Technique) and CPM (C ritical Path Method), the p r o je c t manager can perform h is/her major resp on sib ilities as mentioned above, in a way that is e ffe c t iv e ,
e ffic ie n t, tlinely and less co s tly , and can obtain a desired
performance le v e l
In the following se ctio n s, the development o f CPM and PERT, areas o f applications and advantages are cited.
1 . 5 DEVELOPMENT OF THE NETWORK PLAN CONCEPT
Essentially, networks are techniques to aid manage merit in the
planning and c o n tro l o f p rojects. In one sense the network is only a graphical rep resen ta tion that shows the precedence relationsh ips.t6] The network concept has developed in an evolutionary way ov er many
years. In 1956, Flaglet^] wrote a paper (published in 1961) on
probability based toleran ces in fo re ca s tin g and planning, which was, in a sense, the forerunner to the development o f PERT.
PERT was developed in the US Navy during the late 1950s to
a cce le ra te the development o f the Polaris F leet B allistic Missile. In these stu dies, a ctu a l c o s ts were two to three times the e a r lie s t estiinated c o s ts , and the p ro je c t durations averaged 40 to 50 percent g re a te r than the e a r lie s t estim ates. ti2]
In these studies, it was recognised that a more appropriate p r o je c t was needed in the form o f an integrated planning and c o n tro l system f o r the Polaris Weapons System program. This research p r o je c t was named as Program Evaluation Research Task By the time o f the f i r s t
internal p r o je c t report, it became P irfject Evaluation and Review
Technique (PERT)S'^^'i
This in itia l use o f PERT coped with an extremely complex pi'oblem, fu ll o f uncertalrity and open to many unknown iiifluences; ov er .3,000 su b con tra ctors involved in tliis large p r o je c t had to be coordinated,
and PERT provided an adequate means o f communication.1 ] Control
was based on the timing o f the completion o f certa in phases wibliin the p ro je cts, irre s p e ctiv e o f the c o s t involved. Uncertainty in the
duration o f the tasks, due to the considerable amount o f research and development necessary, was introduced to allow : (1) calculations o f probabilities o f acMeving deadlines; and (2) evaluation o f the e f f e c t o f action to ensure such achievement with a lilgh degree o f certainty. [6 1
CPM, on the oth er hand, was developed in 1957 by J. E. Kelly o f the
Remington Rand Corporation and M. R. Walter o f Du Pont to determine
how b e st to reduce the time required to perform routine plant
overhaul, maintenance and con stru ction work In essence, they were in te re ste d in determhiirig the optlinum p r o je c t duration and t o t a l p r o je c t c o s t .[i2]
The pioneering PERT and CPM groups did not know o f each oth er's existen ce until earlj·’' 1959. The major d ifferen ce between the two teclmiques is that CPM does not incorporate uncertainties in a c tiv ity times. Instead it assumes that a c tiv ity times are proportional to the amount o f resou rces alloca ted to them so th at by changing the le v e l o f resou rces the a c tiv ity tines and the p r o je c t completion time can be varied. Thus CPM assumes p rior experience with similar p ro je c ts from wMch the relationships between resou rces and a c tiv ity times are available. CPM then evaluates the t r a d e -o ff between p r o je c t c o s ts and p r o je c t completion time.
E ssentially the network diagram is e ssen tia lly an outgrowth o f the bar chai't wMch was developed by Gantt in the context o f a World War I military requirement. The bar chart is primarily de.signed to c o n tro l the time element o f a program. In particular, bar charts do not readily shov·? works which are c r it ic a l to the achievement o f the
o v e r a ll p r o je c t o b je ctiv e s , nor the degree o f fle x ib ility in the timing o f those a c tiv itie s which are not c r it ic a l Moreover, it is not easy with a bar chart to evaluate the changes n ecessary ш the plan o f action, eith er when a decision is talien to modify works, o r when a work does not achieve, in execution, the planned tiinetables.
Use o f networks has now expanded in a ll types o f p ro je cts to which
network planning and c o n tro l may be applied. That led to a
pro life I'at ion o f mnemonics, names, and approaches, which are a ll based on the same technique. They are : Programme Evaluation Procedures (PEP) ; C ritica l Path Analysis (CPA) ; and computer trade--names, such as L e a st-C o st Estimating and Sclieduling (LESS). Such developments were based mainlj'’ on the use o f the network to rniniinise the tiine taken to complete p ro je cts and to evaluate the a ssocia ted c o s ts . A
fu rth er development has been inti'oduced to deal with resou rce
requirements and constrairits by which the planning o f a p r o je c t can be influenced. The network diagramming method was developed in France, and known as the Metra P oten tia l Method (MPM), the GEGB, in England and iri oth er countries. In this method, the diagram conventions are
d iffe r e n t from the conventions used in PERT and CPM.t^i This method
is also caHed precedence diagramming and a ctiv ity -o n -n o d e
diagramming. It is being used more and more frequently, because o f its many advantages ov er the networks with arrows and c ircle s. In a precedence network, the a c tiv itie s are represented with squares or
c ir cle s ; while arrows represen t the lo g ica l interdependence o f
a ctiv ities.(S ee Figure 1) One o f the most important advantages o f a
network using the precedence network is that it does not require
dummy a c tiv itie s to maintain the logic (See Figure 1), but dummy a c tiv itie s can be used to link the p ro je cts instead o f intez'face events. It is also possible to represen t lead-and-lag re stra in ts by the positioning o f arrows rela tiv e to the a ctiv itie s . If the arrow ends on the l e f t o f the a c tiv ity node, it is considered to be a
sta rtin g constraint. Conversely, i f it ends above o r below the
a ctiv ity , the con stra in t is between the end o f one a c tiv ity and the
end o f the next.(See Figure 1) In most pi-ojects, e ffic ie n c y is
obtained by overlapping as many a c tiv itie s as possible. Using an arrow diagram , this can only be represented by breaking up the a c tiv itie s into parts, while the precedence diagr-amming does not require this subdivision. Thus, there can be considerable savlzigs in the number o f a c tiv itie s that have been dz'awn. The represen tation o f a c tiv itie s witldn boxes is e a s ie r to understand than the arrows concept. It is much simpler to draw the a c tiv itie s on the network as they have been lis te d and to connect the arrows (con strain ts) later. Because dummy a c tiv it ie s are not needed on the diagram, and because a c tiv it ie s can be entered hidependently o f the positions o f the oth er a c tiv itie s , tills method o f preparing networks Is particularly advantageous a t the planning stage o f a p roject. Any modification o f the network can be done very simply and quickly without many a ltera tion in the diagram. A
disadvantages o f the precedence networks is that events are
elliriinated.[6]5t[ii]
Arrow Diagram Precedence Diagram
(T>A<2> ^
FIGURE 1 - The R epresentation o f Arrow and Precedence Diagrams
1 . 6 AREAS OF A P P L IC A T IO N
The major diffez-ence between the PERT and CPM techniques is that
originally the time estim ates fo r the a c tiv itie s were assumed
determ inistic in CPM and prob ab ilistic in PERT. PERT is used in R&D or ju s t development pz-ojects that th eir a c tiv itie s az'e not determ inistic.
Therefore, PERT is e v en t-orien ted rather than a ctiv ity -o rie n te d . In
PERT, funding is normally provided fo r each event achieved because incremental funding along the a c tiv ity line has to be based upon
percent complete.LS J
Reseaz’ch and development programs range from puz'e research,
applied research, development, to design and production engineering. While PERT is most u se fu l in the middle o f tids spectrum, variations o f it are now being used in the production end o f this spectrum. PERT is not p articu larly u se fu l in pure research.
Maintenance and overhaul procedures, an area in which CPM was
in itially developed, continues to be a most pz'oductive area o f
application o f c r it ic a l path methods. Construction type p ro je c ts
continue to be the la rg e s t iridividual area iri wMch these methods
are applied.nz]
Moz'e recen t applications o f c r it ic a l path methods include the
development and marketing o f new products o f a ll types, such as new automobile models, food pz’oducts, computez· pz"ograms, and Broadway plays. It can also be applied to complex su rgica l operations.
In addition to an increase in the v a riety o f applications o f c r it ic a l
path methods, they are being extended to answer questions o f
irxcreasmg sopFiis bication. The Important problem o f re.eource
coa etra in ts has been s u cce ssfu lly expanded to include multiple
resou rce types a s so cia te d with multiple p ro je cts. Cost control,
p r o je c t bidding and incentive contractin g are also areas where
sign ifican t developments are taking place.[12]&[io]
1 . 7 C R IT IC A L PATH METHOD AND IT S ADVANTAGES
CPM networks attempt 'to build the entire p ro je c t "on paper" a t a
v e r y early stage o f the p roject. In a certa in sense, CPM is to
p r o je c t management what modeling o r simulation is to economic
studies, p rocess con trol, tran sp ortation problems and plant design. Actually, output from the CPM e f f o r t is only a t o o l to be used by the p r o je c t managers to guide and c o n tr o l the tline and d irection o f a p roject. It must be used as a t o o l and not misused as a weapon. Let us reemphasise th at CPM is only a tool; it cannot and will not replace the su b je ctiv e judgement o f people. CPM networks are pieces o f paper that, in themselves, accomplish nothiig, and the computer is only a f a s t ca lcu la to r that does what humans t e l l it to do. To be a u sefu l took the logic networks and durations must r e fle c t rea lity as c lo s e ly as possible and be contiriuously revised to make them currently accurate. In utiliai'ig the computer printout fo r analysis and action, i t is important to remember that Early and Late S ta rt and Finish dates rep resen t the e a r lie s t and la t e s t time a a c tiv ity can be s ta rte d and completed only i f the planning logic is c o rre ct. Depending upon whether externally Imposed schedule dates are involved on the p r o je c t o r not, the T otal Float may run from negative values through
zero and on to p ositiv e values. Planners generally consider that
anything negative through sero and up to p ositiv e (plus) 10 to 30
days flo a t represen ts a poten tially c r it ic a l chain o f a c tiv itie s that should be watched by the p ro je c t rrianagerrjent.t2],[? 3®;[8]
The main determinant o f the way PERT and CPM networks are
analysed and interp reted is whether a c tiv ity time estim ates are
p rob a b ilistic o r determ inistic. If duration estim ates can be made with
a high degree o f confidence that actu al times will not d iffe r
significantly, the estim ates are determ inistic. On the oth er hand, i f
estim ated biines are su b je ct to variation, the estim ates are
probabilis tic,[ 16 4 3
The lis t o f advantages that one might expect from the use o f c r it ic a l path methods fo r planning and supervision o f p ro je cts is in the following :
1. Planning : C ritica l path methods f i r s t require the establishment o f p r o je c t o b je c tiv e s and sp ecifica tion s, and then provide a r e a lis t ic and disciplined basis fo r determining how to attain these o b je c tiv e s,
considering pertirient tine and resou rce constraints. It reduces the
risk o f o v e rlo o k iig tasks n ecessa ry to complete a p roject, and also it provides a r e a lis t ic way o f carrying out more long-range and
detailed planniig o f p ro je cts, including their coordination a t a ll
levels o f management.[i2 3
2. Communication : CPM provides a clear, concise, and unambiguous way
o f documenting and communicating p r o je c t plans, schedules, and tine and c o s t performance.
3. Psychological - CPM, If properly developed and applied, can encourage a team feeling. It is also very u.seful in e.s tablisliing .schedule objective.s th at are mo.st meaningful to operating per.sonnel, and in the delineation o f re.spon.sibllitie.s to achieve the.se scheduled o b je c tiv e s .[12 3
4. Control : CPMs fa c ilita te the application o f the principle o f management by exception by identifying the most c r it ic a l elements in the plan, focusing management a tten tion on the 10 to 20 percent o f the p r o je c t a c tiv itie s that are most constrainirig on the schedule. It continually defines new schedules, and illu stra te s the e f f e c t s o f tech nical and procedural changes on the o v e ra ll schedule.[i2 ]
d-Tzalning : CPMs are u sefu l in training new p ro je c t managers, and in the indoctrination o f oth er personnel that may be connected with a p r o je c t from tirrje to time.
6 .Cost Control By Compute!'’ Popescu (in 1977) a sse rte d that good
planning and c o s t co n tro l by the help o f computer means savings. CPM
is an information system - the savings occu r only when the
information is used effectiv elj-' by p r o je c t managers. CPM-cost is an
advanced teclmique in planniiig. O'Brien (m 1971) summarised the
advantages o f resou rce planning and c o s t c o n tro l to show that a t o t a l o f 2.75% o f t o t a l p ro je c t c o s t is su bjected to net savings if such a method is applied (see Table l).[i3 3
Additional Savings to Savings to Net
Cost co s t. con tra ctors. owne r, savings.
as a % as a % as a % a.s a %
C ost c o n tro l 0.10 0.25 0.50 0.65
fo re ca s tin g
C ost expediting 0.10 0.65 1.60 2.15
T ota l 0.20 0.90 2.10 2.80
TABLE 1 -- Costs and Savings
For a s u c c e s s fu l Implementation, CPM payment must be assumed by the owner. In the end, he o r she gains time and money through the use o f
CPM-cost c o n t r o l A key fa c to r in a ll s u c c e s s fu l applications is
per,sonnel training from foremen, fie ld residents, up to the top
management level· A fter the f i r s t co n ta ct with CPM-cost control· almost every co n tra cto r agrees th at it provides the means fo r b e tte r planning and c o s t control·
1.8 PURPOSE OF THE THESIS
The large drinking water treatm ent plant p ro je cts that are defined in the s e c tio n o f the drlnkiiig water treatm ent p la n t are comprised o f
a s e t o f many d iffe re n t and integrated a c tiv itie s . All these
a c tiv it ie s must be sequenced very well to (1) complete the p r o je c t a t a given time, (2) fo r e s e e possible troubles in advance, and (.3) give
the coordination and control· fa c ilitie s to the pz'oject manager in ord er to cornpiete, and co n stru ct the p ro je c t on tline. Moreover, all· advantages that are mentioned in the s e ctio n o f Critical· Path Method and its advantages, are obtained by CPM.
As mentioned in the s e ctio n o f Areas o f Application, the most
appllcabie and la rg e s t field o f CPM is the con stru ction type p ro je cts,
and the drinkirig water treatment plant p ro je c t is one such
con stru ction p roject.
As a resu lt, the u tilisation o f CPM in the p ro je c t schedule fo r a
large drinking water treatment plant p ro je c t is very u se fu l and
economical as mentioned above. Thus, the purpose o f th is th e sis i s to
show how CPM can be applied to a given pix>Ject schedule f o r a model drlnkliw water ti'eatment pla n t p r o je c t
A large drinking water treatment plant p ro je c t that is equipped fo r serving approximately 650,000 people, is assumed. A schedule o f it was calcu lated by CPM, and its network and bar chart schedules o f
works were prepared (See Appendix B, C and D) by the use o f
PRIMAVERA PROJECT PLANNER that is p r o je c t management and c o n tro l
softw are (See Appendix A to get information about the planner).
1 . 9 OUTLINE OF THE T H E SIS
In the f i r s t chapter, water treatm ent and its o b je ctiv e s are cited. Then, the defin ition o f p r o je c t management, the resp on sib ilities o f a p r o je c t manager and the development o f network plan concept are
explained. The requirement o f CPM is underlined fo r the p r o je c t
management o f a large drinking water treatment plant p ro je c t because
o f its advantages. In the second chapter, some terms and their
definitions fo r use in the application are defined and p ro je c t
calendar, a c tiv itie s and th eir estimated durations are specified.
Schedule rep orts and network logic diagram fo r c r it ic a l a c tiv itie s are prepared. For the p r o je c t manager, the required performance c rite r ia to handle the p r o je c t e ffe c t iv e ly in the estimated time are explained. In the third and fou rth chapters, discu ssion and summary, conclusion and recommendations are made.
2 APPLYING CPM TO A D RINKING WATER TREATMENT PLANT PROJECT
2 , 1 D E F IN IT IO N S
Some terms fo r use jjri the computer program application and its rep orts are used. These terms and their definitions are as follows : A c tiv ity : Any task or operation requlririg tline and possible oth er resou rces that i t must be carried ou t in order to complete a p roject. Bar Chart · The presentation o f timings o f a c tiv itie s by means o f bars drawn agairist a common tim e-scale, which can be a re la tiv e or an absolute scale.
Duration : The length o f tiine required to complete an a ctiv ity . Flrdsh Date (FIN DATE) : An end date fo r the p roject.
Free F loat : The number o f days that an a c tiv ity 's early s t a r t may be delayed without delaying the earlj^ s t a r t o f the s u cce s s o r a ctiv ity .
Lag Days : The number o f the days between the finish o f one a c tiv ity and the finish o f a subsequent a ctiv ity .
Late F inish (LF) : The time (or date) by which an a c tiv ity must finish. Late S ta r t (LS) ■ The time (or date) by which an a c tiv ity must sta rt. Precedence R elationship : The relationsliip between an a c tiv ity and its s u cce sso rs . Tliree types o f relationships can be expressed in the network :
a. Conventional (C) : The s u cc e s s o r may begin only upon the finish o f the currently displayed a ctiv ity . This is also called a fin is h -t o -s t a r t
relationship. A conventional relationship may o r may not include a time lag between the finish o f the displayed a c tiv ity and the s t a r t o f its su cce sso rs .
b. S t a r t - t o - S t a r t (S) : The curren t a c tiv ity and its s u c c e s s o r mus t s t a r t eith er a t the same time o r the su cce sso r's s t a r t date must lag behind the s t a r t date o f the currently displayed activity.
c. F in ish -to -F in ish (F) : The currently displayed a c tiv ity and its s u c c e s s o r must finish eith er a t the same time, that the finish date
o f the s u cc e s s o r must lag behind the finish o f the currently
displayed act.ivity.
Schedule : The sp e cifica tio n o f the time (or date) a t or on wMch a c tiv itie s are planned to s ta r t, the a c tiv ity durations, and the resou rces allocated.
S ta r t Data : The day on wMch a p r o je c t can begin.
Total F loat : The d ifferen ce between the early finish date and late
finish date.s. It represen ts the number o f day.s that the a c tiv ity can be delayed without a ffe ctin g the remaining scheduled events.
Workday : The date on which an a c tiv ity begins o r ends rela tiv e to the p r o je c t calendar. A ctivities are always assumed to s t a r t on the morning o f a workday. Siinilarly, an a c tiv ity is always a.ssumed to finish a t the end o f the workday. An a c tiv ity having one day's duration will s t a r t and end on the same workday.
2 . 2 PROJECT CALENDAR
P ro je ct calendar defines the available workdays during the p ro je ct's period o f performance. 1440 workdays fo r the model water treatment
plant p r o je c t according to the experience, is estiinated. These
workdays is taken about between 1400 and 1500 workdays fo r most
water treatment plant p rojects.tis ] These estimated workdays are
valid under the condition that no financial problems and/or unexpected d isa ste rs happen fo r the relevant pr-oject. The s t a r t date o f the p r o je c t is sp e cifie d on 12''-h December 1988 and the finish date, on 21st November 1992. 7 workdays in a week without any holidays during the performance o f the p r o je c t are assumed.
In the next section , the p ro je c t a c tiv itie s and th eir estimated durations are specified.
2 . 3 S P E C IF Y IN G THE PROJECT A C T I V I T I E S AND THEIR ESTIMATED DURATIONS
A number o f 5.3 a c tiv itie s and 84 interrelationships fo r the
a c tiv it ie s were sp e cifie d (See Appendix B 2 and B 3). All sp ecified a c tiv itie s are shown on Schedule Reports in Appendix B 3 with their relevan t p red ecessors and s u cce sso rs . The durations o f these 53 a c tiv it ie s and lag times o f a c tiv itie s before or a ft e r preceding or
succeeding a c tiv itie s were estirriated according to the experience
based on three previous p ro je cts that are siinilar to this p r o je c t with r e s p e ct to th eir capacity and teclm ological p rocesses that are used iri the water treatm ent plant.
When developing the plan, the p r o je c t was broken down into 53
individual a c tiv itie s , each representing a task to be accomplished. Each task was iden tified as an a c tiv ity title . The execution o f the
ta sk will consume tiine as well as resou rces such as manpower,
material, equipment, and cash flow. Wliile defining the place o f an a c tiv ity in the p ro je ct, the following questions were answered :
-What oth er a c tiv itie s must be completed so that this a c tiv ity can s ta r t ?
-What oth er a c tiv itie s can be done while this a c tiv ity is being
performed?
-What a c tiv itie s cannot s t a r t until a ft e r this a c tiv ity has been completed?
According to these questions, the precedence diagramming method was used fo r describing a ctiv ity relationships. The precedence diagramming method is more flexible than the arrow diagramming method because the planner is not limited to fin is h -to -.s ta r t relations Mps. There are
numerous scheduling situ ation s where one a c tiv ity overlaps with
another. The precedence relationships o f a c tiv itie s were defined in three types o f relationship. Most a c tiv ity relationships were defined as a Conventional (C) o r a S ta r t-to -.S ta r t (S). Other ones were defined as a F inish -to-F in ish (F).(See the schedule re p o rt in Appendix B .3) Durhig the p r o je c t planning stage, delays could not be Included within a c tiv ity durations and oth er con stra in ts from oth er a c tiv itie s could not considered.
In Appendix B 3 , a p r o je c t schedule rep ort displays the detailed p red ecessor and s u cc e s s o r a c tiv itie s fo r each a c tiv ity in the p ro je c t schedule. In tlris report, the a c tiv ity title , the estimated duration o f
a ctiv ity , its predeccors and su cce sso rs , its precedence relationships, and lag times among them are seen very easily. In the presen tation o f p red ecessor and s u cc e s s o r a c tiv itie s the following codes are used : FRED is the p red ecessor a c tiv ity
SUCC is the s u c c e s s o r a c tiv ity
* indicates a c r it ic a l relationship between an a c tiv ity and its
p red ecessor o r su cce sso r.
In numbering a c tiv itie s , the following principles are used.
a. A ctivity numbers a t the beginning and end o f an a c tiv ity should be unique.
b. The number o f the en d -a ctiv ity should be g rea ter than the number o f the begim in g-a ctivity.
c. Gaps should be l e f t in the sequence o f a ctiv ity numberiig, to allow fo r subsequent insertion o f a c tiv itie s .
2 . 4 SCHEDULE PRESENTATION
A fter sp ecifyin g the a ctiv itie s , their precedence relationships and a c tiv ity durations in the p ro je c t the planner can begin to schedule a c tiv itie s by using the p ro je c t calendar. In this study, the schedule calculations were done by the use o f the Prirnavera P r o je ct Planner (See Appendix A). For each a ctiv ity , early and late s t a r t and finish dates were scheduled. All scheduled a c tiv itie s are shown on each
schedule and bar chart reports in Appendices B 1 , and C 1 , C 2.
2 . 5 C R IT IC A L PATH ID E N T IF IC A T IO N
Having calcu lated the early and late event tirne.e fo r each a ctiv ity ,
the schedule rep orts were prepared.(See schedule rep orts in
Appendix B) The schedule reports show each a ctiv ity o f early s ta rt,
early finish, late s tai’t, la te finish and t o t a l float. T otal flo a t fo r an a c tiv ity represen ts the number o f days that the a c tiv ity can be delayed without a ffe ctin g the remaining scheduled a ctiv itie s . The flo a t is valuable in regulating the use o f labor, materials, c o s ts , and
oth er resou i'ces and in timing the a c tiv itie s with which it is
associated.
C ritica l a c tiv it ie s c o n tro l tlie o v e ra ll timirig o f the p roject. Together, they make up one o r more continuous chains o f aero flo a t a c tiv itie s running from the sta rtin g a c tiv ity to the finishirig a ctiv ity iri the schedule.
N on -critica l a c tiv itie s have p ositiv e flo a t because there is some
slack, o r flexib ility , in their sta rtin g dates. However, lack o f
progress on n o n -c ritic a l a c tiv itie s can cause them to become c r it ic a l in the fu ture because o f having lirrdted fre e or t o t a l flo a ts.
In tills study 12 a c tiv itie s were found as c r it ic a l a c tiv itie s with a
aero t o t a l .float.(See Network Logic Diagram For C ritica l Path in
Appendix D 1) They are "Order to Commence Work", "Planning and Work
Schedule", "Functional Plan, Predesign and Hydraulic Calculation",
"Plant Working Designs, Technological Plans and Erection Designs",
"Final Design Report and Hydraulic Report", "Treated Water and F ilters
Construction", "Treated Water and F ilters Mechanical Installation",
"Treated Water and F ilters E lectrica l Installation", "Setting to Work", "Temporary Acceptance", "Period o f Guarantee" and "Final Acceptance".
This c r it ic a l chain o f a c tiv itie s (See Appendix D 2) should be watched
by a p r o je c t manager to iinplement the p ro je ct during the e.stimated time.
3 D IS C U S S IO N
In this th esis, CPM is applied to the p ro je c t o f a driiiking water treatm ent plant which has a capacity o f 250,000 m3/day, and serv es approximately 650,000 people. When developing the plan, the p r o je c t was broken down into 53 individual a c tiv itie s , each representing a task to be
accomplished. Each ta sk was identified as an a c tiv ity title . The
execution o f any a c tiv ity consumes time as well as resou rces such as
manpower, material, equipment, and cash flow. The precedence
reiationsM ps o f a c tiv itie s were defirxed in three types o f relationship.
Most a c tiv ity rela tions Mps were defined as Conventional (C) or
S t a r t -t o -S t a r t (S). The oth er ones were defiried as F inish-to-F inish (F)
(See Appendix B 2 and B 3). Duriiig the p r o je c t planning stage, delays
could not be included witliin a c tiv ity duration and oth er constraints from oth er a c tiv itie s could not be considered. A fter scheduling the p roject, fr e e flo a t and t o t a l flo a t o f a c tiv itie s are found (See Appendix B 1 and B 2). A ctivities can be delayed according to th eir fre e flo a t and t o t a l flo a t in the relevan t chain o f a c tiv itie s . Then the c r it ic a l a c tiv itie s are defined according to th eir t o t a l flo a t iri the project. These c r it ic a l
a c tiv itie s should not be delayed to implement the p r o je c t on the
estiinated time. But n on critica l a c tiv itie s which have large fre e flo a t or t o t a l flo a t, may be delayed iri the chain o f a ctiv itie s . With the help o f the schedule (See Appendix B 1 and B 2) containing the iden tified c r it ic a l a c tiv itie s , the p r o je c t manager who is responsible fo r perforrnmg the
relevan t p r o je c t a c tiv itie s and completing the p ro je c t within the
estim ated p r o je c t period, implements these c r it ic a l a c tiv itie s without
allowing any delaying. Therefore, p ro je c t manager,s .should not a lloca te the manpower, material, equipment, and cash flow without talking into account the fre e flo a t situ ation s o f a c tiv itie s being planned to perform the a c tiv itie s under th eir respon sib ilities on time according to the planning o f the a c tiv itie s . Thus, early information about a c tiv itie s to be performed in the coming period, are provided fo r tlie p ro je c t managers
with the help o f tills p r o je c t schedule. The p ro je c t manager can
cooi'dinate a ll the scheduled a c tiv itie s without any problems such as spending extra time. The p ro je c t schedule gives the p ro je c t manager the required performance measures how to handle this p ro je c t as well
In the curren t p ro je ct, the a c tiv itie s that have fre e flo a ts are
"E lectrica l Predesign", "Topographical and Geotechnical Survey",
"In frastructu re (Hydraulic) Construction", "Infrastructure Technical
Gallery Construction", "S ta ff Housing Construction", "Guard House
Construction", "Administration Building Construction", "Spare Equipment
Delivery", "C la rifier E lectrica l Installation", "Workshop and Energy
Building Ins tallation", "Admiriis tra tlon Building Main Control Panel
Installation", "Raw Water Inlet and A erator Mechanical Installation",
"Chemical Building E lectrica l Installation", "Wash Water Holding Tank
E le ctrica l Installation", "Raw Water Inlet and A erator E lectrica l
Installation", "Wastewater Treatment Plant E lectrica l Installation",
"Thickeners and Sludge Station E le ctrica l Installation", and "General
Infrastructure". In accordance with the precedence o f t o t a l flo a ts , these a c tiv itie s can be delayed without delaying the early s t a r t o f the s u c c e s s o r a ctiv ity . The resou rce a lloca tion o f these a c tiv itie s can moved to the c r it ic a l a c tiv itie s to be implemented on estimated tlirje, by
delaying them with th eir fre e flo a ts . These resou rces may be manpower, material, equipment and/or cash flow. Resource a lloca tion depends on the situ a tio n and the limitations o f the project. In order to firiish the p r o je c t within the estim ated time, the i-esource a lloca tion should be organised according to the p ro je c t schedule by the p ro je c t manager.
The a c tiv itie s that are found to have p ositive t o t a l flo a ts are "Civil and A rch itectural Predesign", "Set up Site", "Civil Work and A rch itectural
Application Designs", "Heating, Ventilation and Sanitary Installation
Designs", "E lectrica l Application Designs", "Import Permission fo r
Equipment", "F irst Import Delivery", "Second Import Delivery", "TMckeners and Sludge S tation Construction", "Wash Watez' Holding Tank Construction", "Raw Water Inlet and A erator Chambez' Construction", "Flash Mixer and C la rifier Construction", "Chemical Building Construction", "Workshop and
Energy Building Construction", "In frastructu re Roads", "Wastewater
Treatment Plant Construction", "Wash Water Holding Tank Mechanical
Installation", "Clai’ifie r Mechanical Installation", "Chemical Building
Mechanical Installation", "Wastewater Treatment Plant Mechanical
Installation", and "TMckeners and Sludge Station Mechanical Installation". These a c tiv itie s may be delayed in accordance with th eir succeeding a c tiv it ie s that have fre e flo a ts. Therefore, these a c tiv itie s have t o t a l flo a t in the chain o f a ctiv itie s . In a certa in chain o f a c tiv itie s , each a c tiv ity shows the same t o t a l flo a t because o f the fre e flo a t o f the la s t succeeding a c tiv ity in the chain o f the a ctiv itie s . Therefore, i f this t o t a l flo a t is used fo r the f i r s t a c tiv ity in the logic chain o f a c tiv itie s , then the remaining a c tiv itie s in the logic chain, should not be delayed to iinplement the p r o je c t on the estimated time because under
this situ ation , the remaining a c tiv itie s are as c r it ic a l a c tiv itie s . Therefore, these a c tiv itie s that represen t a logic chain o f a c tiv itie s , should be watched in this way, by the p ro je c t manager.
4 CONCLUSION AND RECOMMENDATIONS
In this th esis, CPM is applied to a large drinking water treatment
plant p r o je c t that has a capacity o f 250,000 m3/day, and serves
appi'oxlmately 650,000 people. F ifty -th re e a c tiv itie s and 83 relationships
among these a c tiv it ie s were sp ecified fo r this p roject. For each
a ctiv ity , early and late s t a r t and finish dates were .scheduled by the
use o f Primavei-a P r o je ct Pla.nner. Twelve a ctiv itie s were found as
c r it ic a l a c tiv itie s with zero t o t a l flo a ts. They are "Order to Commence
Work", "Plannnig and Work Schedule", "Functional Plan , Predesign and
Hydraulic Calculation", "Plant Working Designs, Teclm ological Plans and Erection Designs", "Fitual Design Report and Hydraulic Report", "Treated Water and F ilters Construction", "Treated Water and Filters Mechanical Installation", "Treated Water and F ilters E lectrica l Installation", "Setting to Work", "Temporary Acceptance", "Period o f Guarantee" and "Final Acceptance". These 12 c r it ic a l a c tiv itie s are found to be r e a lis tic , because, in the application o f sin ila r p ro je cts, these a c tiv itie s played a major c r it ic a l role in the completion o f the p ro je c t within the desired scheduled time;
"E lectrica l Predesign", "Topographical and Geotechnical Survey",
"In fra stru ctu re (Hydraulic) Construction", "Infrcistructure Teclmical
Gallery Construction", "S ta ff Housing Construction", "Guard House
Construction", "Administration Building Construction", Spare Equipment
Delivery", "Clarif.ier E le ctrica l Installation", "Workshop and Energy
Building Installation", "Administration Building Mail Control Panel
Installation", "Raw Water Inlet and A erator Mechanical Ins baliation".
"Chemical Building E le ctrica l Installation", "Wash Water Holding Tank
E le ctrica l Installation", "Raw Water Inlet and A erator E lectrica l
Installation", "Wastewater Treatment Plant E lectrica l Installation",
"Thickeners and Sludge Station E lectrica l Installation", and "General
Infrastru cture" a c tiv itie s have fre e floa t. These a c tiv itie s and their preceding a c tiv it ie s may be delayed without delaying the early s t a r t o f
the .succe.s.sor activltie.s o f them, because o f the p riority o f the
c r it ic a l a c tiv itie s .
"Civil and A rch itectu ral Predesign", "Set up S ite”, "Civil Work and
A rch itectu ral Application Designs", "Heating, Ventilation and Sanitary
Installation Designs", "E lectrica l Application Designs", "Import Permission
fo r Equipment", "F irst Import Delivery", "Second Import Delivery",
"Thickeners and Sludge Station Construction", "Wash Water Holding Tank Construction", "Raw Water Inlet and A erator Chamber Construction", "Flash
Mixer and C la rifier Construction", "Chemical Building Construction",
"Workshop and Energy Building Construction", "Infrastructure Roads",
"Wastewater Treatment Plant Construction", "Wash Water Holding Tank
Mechanical Installation", "C larifier Mechanical Installation", "Chemical
Building Mechanical Installation", "Wastewater Treatment Plant Mechanical Installation", and Thickeners and Sludge Station Mechanical Installation" a c tiv itie s have t o t a l flo a ts . These a c tiv itie s may be delayed providing that t o t a l flo a ts o f th eir succeeding and preceding a c tiv itie s and fre e flo a ts o f succeeding a c tiv itie s iri the relevant chain o f a c tiv itie s , should be watched by the p r o je c t manager to implement, the p ro je c t on the estim ated time.
REFERENCES
[1] American S ociety o f Civil Engineers , American Water Works
A ssociation and Conference o f State Sanitary Engineers : Water Treatment
Plant Design , American Water Works A ssociation , Inc. , NY , 1969.
[21 Davis , E.W.(Editor) : F iv je c t Management : Teclmiques , A pplications ,
and Managerial Issu e s , 2nd. Ed. , Industrial Engineering & Management Press , USA , 198.3.
[3] Degi'emont : Water Tzeatment Handbook , 5th. Ed. , Firmin-Didot S.A. ,
Paris , 1979.
[4] Fersko--Weiss , H. "A P ro je ct Management Primer", PC Magazine ,
November 15 , 1988 , page 187-191.
[5] Flagle , C. D. "Probability Based Tolerances in F orecastbig and
Planning" , The Journal o f In d u stria l Englneei'Mig , Vo 1 12 , No : 2 , 1961 , page 97-101.
[6] Hoare , H. R. P io je c t Management Using Netwoik A nalysis ,
Mc.Graw-Hm Book Co. (UK) Ltd. , London , 1973.
[7] Jen ett , E. "Experience with and Evaluation o f C ritica l Path
Methods" , Chemical Engineering , February 10 , 1969.
[8] Kelley' , J. E. and Walker , M. R. : "Ci'it leal-P ath Planning and
Scheduling" , Pix^ceedim Of The E astern J o in t Computer Conference , 1959
[9] Kersner , H. : P x e je c t Manageraent a Systems Appx'oach to Plan2ii.ng ,
Scheduling and Controlling , 2nd. Ed. , Van No.strand Reinhold Co. ,
NY ,1984.
[10] Levy , F. K., Thompson , G. L. and Wiest , J. D. :"The ABC.s o f the
C ritica l Path Method" , Harvard Business Review , Septem ber-October ,
1968.
[11] Lockyer , K. G. : C ritica l Path A nalysis and Other P ro je c t Network
Teclnilques , 4th. Ed. , Pitlirnan Pub. Ltd. , Great Britain , 1986.
[12] Moder , J. J. , Phillips , C. R. : P ro je c t Management with CPM and
PERT , 2nd. Ed. , Van Nostrand Reinhold Co. , NY , 1970, page 5-18.
[13] Popescu , C. M. : "CPM-Cost C ontrol by Computer" , Journal o f the
Construction D ivision , ASCE , December , 1977.
[14] Raviiidran , A., Phillips , D. T., and Solberg , J. J. : Operatloîis
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[15] S irer , i : "Su Tasviye T esisleri" , DSi Bülteni , No : 205 , June , 1978 , page 14-18.
[16] Stevenson
IRWIN , 1986.
W. J. Pix>duction/Operatdons Management , 2nd. Ed. ,
APPENDICES
APPENDIX A :
PRESENTATION OF THE PRIMAVERA
Primavera is a complete planning and scheduling t o o l fo r p ro je c t
managers that helps evaluate and analyse schedules and resou rce requirements fo r a ll types o f p rojects.
The Primavera P r o je ct planner (P.3) is a comprehensive p r o je c t management softw are system that gives managers complete co n tro l o v e r large and small p rojects. P3's extensive capabilities Include c r it ic a l path scheduling, resource a lloca tion and leveling, and c o s t c o n t r o l
P3 is a fully in tera ctive, command-driven system. P3 fea tu res an advanced data entry mode fo r easy iriput and updating o f large, complex networks.
P3 handles single and multiple p ro je cts containing up to 10,000 a c tiv itie s . Some o f the more important fea tu res are liste d below.
S c h e d u lin g
-U tilizes C ritica l Path Method fo r scheduling
“iiuppurte
tiFPei 0Í isliÉite GileiiMtiíMi leiio: i
Lbj^ld
-Analyae.s and d e te cts open ends and a c tiv ity loops prior to
schieduling.
-T a rg e t planning fu lly supports performance measurement.
-A c tiv ity coding fo r organising p ro je c t data such as respon sibility assignments and work breakdown stru ctu re s (WBS).
R e s o u r c e A l l o c a t i o n And L e v e l i n g
-96 resoux'ces per p ro je c t ; 6 per activity.
-C alculates and levels resou rce usage, simplifying resou rce smoothing and alleviating con flicts.
-Allows resou rce unit prices to vary over time account fo r inflation.
C o s t C o n t r o l
-Automatic costin g o f resource usage.
-U ser-defin able calcu lation o f resou rce units and c o s ts when updating.
-Computes ecirned value fo r pex'formance measurement.
A d d i t i o n a l F e a t u r e s
-O n -screen tabulax' view o f a c tiv ity schedules.
-O n -screen bar charts, r e s o u r c e /c o s t histograms, and cumulative curves.
-E xtensive custom reporting capabilities, including comprehensive
s e le ctio n and sortin g o f p r o je c t datci.
-Data export to Lotus 1-2-3, d.BASE III, ASCII file, and other spreadsheet/data base softw are packages.
-B’eatures advanced data entry mode fo r automated input and update o f re p e titiv e o r large networks.
APPENDIX B : SCHEDULE REPORTS
In the rep orts, the to lie wing codes are used ;
Date Code d irects Priinavera to use a particular s e t o f schedule dates in plottixig schedule bar charts. For a single bar, the possible date codes are :
EE : Early s t a r t through early finish dates only LL : Late s t a r t through late firiiah dates onlj;'
EL : Early and late dates, but show early dates i f there is an overlap
LE : Late and early dates, but show la te dates i f there is an overlap
APPENDIX B 1 :
PROJECT SCHEDULE SORTED BY EARLY START AND TOTAL FLOAT
This rep ort displays the a ll a c tiv itie s that are s o rte d by Early S ta rt and then T otal Float in the p ro je c t schedule.
REPORT DATE 12EEB89 RUN HO. 77 ...PROJECT SCH EDOLE—-PROJECT SCHEDOLE REP.(vith log)-Sorted by ES,TF
ATA COHSTROCTION CO. PRIHAVERA PROJECT PLAHHER HATER TREATHEHT PLANT PROJECT START DATE 12DEC88 FIN DATE 21NOV92 DATA DATE 12DBC88 PAGE NO. 1
АСТ1УШ ORIGREN DOR DOR PCT ACTIVITT DESCRIPTION CODE EARLY START EARLY LATE
FINISH START FINISH FLOATLATE TOTAL
1 0 0 0 10 70 70 0 23 90 90 0 11 150 150 0 22 90 90 0 25 250 250 0 31 90 90 0 12 120 120 0 20 90 90 0 35 290 290 0 26 180 180 0 44 240 240 0 61 530 530 0 45 430 430 0 28 250 250 0 27 120 120 0 36 0 0 0 55 490 490 0 47 300 300 0 52 450 450 0 51 250 250 0 49 300 300 0 ORDER TO COHHENCE HORK 12DEC88
SET OP SITE 22DEC88
FUNCTIONAL PLAN,PREDESIGN 4 HYDRAOLIC CALCULAT. 27DEC88 TOPOGRAPHICAL A GEOTECilCAL SURVEY 11JAN39 PLANT HORRIHG DES. .TECH. PLANS 4 ERECTION DESIGN 7HAR89 LEVELLING,SITE ACCESS ROADS , FENCING 22HAR89
CIVIL 4 ARCHITECTURAL PREDESIGH 6AFR39
ELECTRICAL PREDESIGN 6HAY89
FINAL DESIGN REPORT AND HYDRAULIC REPORT 15JUL89 CIVIL HORK 4 ARCHITECTURAL APPLICATION DESIGNS 4A0G39 RAH HATER INLET 4 AERATOR CHAHBER CONST. 13SSRi9 TREATED HATER TANK AND FILTERS CONSTRUCTION 130CT89 FLASH HIKER AND CLARIFIER CONSTRUCTION 130CT89
ELECTRICAL APPLICATION DESIGNS 130CT89
HEATING,VEHTILATI0N4SANITARY INSTALLATION DESIGN 2N0V89
DDHHY 2NOV89
INFRASTRUCTURE ROADS 2NOV39
CHEHICAL BUILDING COHSROCTION 2NOV39
STAFF HOUSING CONSTRUCTION 2NOV89
INFRASTRUCTURE TECHNICAL GALLERY CONSTRUCTION 2HOV89 HORKSHOP AND ENERGY BUILDING CONSTRUCTION 2NOV89
12DECS3 12DEC88 19FKB39 12DEC38 21HAR89 12DEC39 25HAY89 27DEC88 10AFR89 10FEB90 11NOV39 19JUN39 12HAR90 3AUG39 15JUL39 3A0G89 30APR90 15JUL89 30JAN9U 12NOV39 10HAY90 30JUL90 26HAR91 130CT89 16DEC90 21JAN90 19JUN90 2IAPR90 IHAR90 10FEB90 2NOV89 10FEB90 6HAR91 10FEB9U 28AUG9U 31HAY90 25JAN91 31HAY9U 12DEC88 0 19FEB39 0 1IHAR90 355 25HAY89 U 10HAY90 395 1INOV39 0 9J0N90 355 11NOV39 100 19JUN90 320 10HAY90 100 26HAR91 320 26HAR91 100 26DEC90 190 9JUN90 100 9JUL90 28AUG90 29AUG90 14JUN91 100 26HAR91 210 23AUG91 210 I4FEB91 220 24JUN91 300 APPENDICES Page : 43
