KING%20FAHAD%20UNIVERSITY%20OF%20PETROLEUM%20AND%20MINERALS%20CONSTRUCTION%20ENGINEERING%20

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KING FAHAD UNIVERSITY OF PETROLEUM AND
MINERALSCONSTRUCTION ENGINEERING MANAGEMENT
DEPARTMENTCEM 510

• CONSTRUCTION DELAY COMPUTATION METHOD
• BY Jonathan Jingsheng Shi, Member , ASCE, S.O.
  Cheung and David Arditi, Member, ASCE
• REF
• JOURNAL OF CONSTRUCTION ENGINEERING AND
  MANAGEMENT JAN/FEB,2001 VOL. 127 NO.1
• FEB28,2006

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OBJECTIVEThis paper presents a method for
computing activity delays and assessing their
contribution to project delay. The method
consists of a set of equations, which can be
easily coded into a computer program that allows
speedy access to project delay information and
activity contributions.

• BACKGROUND
• Most problem in construction is delay
• Construction contract contract duration (
  specified period of time) contractor must
  comply to achieve substantial completion within
  this time
• For unexpected reasons contractor fails to
  complete the project within the contract period
• Owner will claim liquidated damages and obtain
  contractual release extension of time
• Delay analysis based on responsibilities delay
  excusable (compensable noncompensable ) and
  inexcusable
• Project delay result from computing activity
  delay
• Delay computation related to as-planned schedule
  contrasts as-built schedule
• Traditional delay analysis method based always on
  CPM analysis on other words any delay on critical
  path delay the project completion
• This method is not based on CPM and no need for
  updating CPM
• Criticality of individual activities change from
  day to day due to delays accelerations which
  means if delay happen then extra effort from
  manager to up date the as-planned schedule with
  daily as-built information

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APPROACH AS

1. Examine the occurrence of delay
2. Method for computing activity delays
3. Method for computing the contribution of activity
   delays to project delay
4. example

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Occurrence of Construction delay

• Activity completion delay to reasons
• Delay in the start of the activity
• Delay in the precedence activities
• Delay in the start of the activity itself for
  some reason
• Extend the duration of the activity

Delay precedence
Late design information
Delay deliveries
Succeeding Not delayed
Project Not delayed
No resources
Delay start
Succeed- ing delayed
Activity delay
Project delayed
Bad weather
Extended activity duration
Mang. decision
Less resources
Change scope
Change Site condition
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Activity Variation

• VSactual start time planned start time
  .....1
• VFactual finish time planned finish
  time....2
• VDactual duration planned duration
  ........................3
• From CPM network following relationship
• Actual finish timeactual start time actual
  duration ...4
• Planned finish timeplanned start time planned
  duration.5
• By subtract 4-5 then Eq 2 can be written
  as
• VF VS VD ...6

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Contribution of Activity Variation to Project
delay

• VP actual completion time - planned completion
  time ( ve 0r ve )
• Two factors
• PDAC MEASURING THE PROJECT DELAY DUE TO
  ACCUMULATED ACTIVITY VARIATIONS CONTRIBUTED BY
  THIS AND ALL ITS PRECEDING ACTIVITIES
• PDA MEASURING THE PROJECT DELAY CONTRIBUTED
  ONLY BY THIS ACTIVITY
• Project delay is realized on the terminal
  activities ..mechanism start from terminals and
  continue backward through intermediate activities
• Terminal activities are the last activities
  that do not have succeedings
• Variation in the completion time of the terminals
  may contribute to project delay
• PDAC actual finish time of the terminals -
  planned project finish time
• PDA min ( VA , PDAC )
• Intermediate activities those succeeding the
  terminals

j
i
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Example Discussion
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Conclusion

• This paper presents a method for computing
  activity delays and assessing their contribution
  to project delay. The method consists of a set of
  equations, which can be easily coded into a
  computer program that allows speedy access to
  project delay information and activity
  contributions.
• This method applicable to any intermediate
  construction stage for evaluating in-progress
  project delay
• Traditional delay analysis method based always on
  CPM analysis require frequent updates of the
  as-built and as-planned schedules in order to
  keep track of the critical paths that may change
  daily. Such updating will require tremendous
  effort for site management. This method depend on
  as-planned schedule as basis of comparison for
  evaluating the variation in the project duration
  does not need to be updated.
• This method is based on the finish-to-start
  relationship which is most common but not
  applicable to start-to-start or finish-to-finish
  relationships in current form , but equations can
  be expanded to these relationship as necessary.