Scheduling

1
Scheduling

• CTC-470

2
Short Interval Scheduling

• Plan manage day to day activities
• Focus on individual activities
• Goal Oriented to get activity done
• Two Categories
• Look Ahead
• Production

3
Look Ahead Scheduling

• Focuses on what needs to be accomplished during
  next time period
• Extract from overall schedule
• More detailed than overall schedule since looking
  at day to day activities
• Must make sure that look ahead schedule matches
  the overall schedule

4
Production Scheduling

• Plan and Schedule one specific activity or group
  of sub activities related to a particular
  construction process
• Good for subcontractor work
• Types of schedules
• Date list, Bar Chart, Network Schedule
• Graphic Schedule, Matrix Schedule, Velocity
  Diagram

5
Production Scheduling

• Date List
• List of Dates used to plan and manage an activity
• Difficult to follow without a narrative
• Figure 9-2
• Bar Chart
• Like a regular bar chart but for sub activities
• Figure 9-3

6
Production Scheduling

• Network Schedule
• More complicated
• More info
• Figure 9-4
• Graphic Schedule
• Easy to read
• Figure 9-5

7
Production Scheduling

• Matrix Schedule
• Good when identical activities with very similar
  sub-activities
• When work is repetitive
• Figure 9-6
• Velocity Diagrams
• Relationship between time and output
• Very effective, easy to read
• Figure 9-7

8
Precedence Diagram Method

• Extension of AON Network
• Allows concurrent activities to overlap
• Restraints not required to model logical
  relationships
• Schedule logic is easier and quicker to develop
• Easier to modify
• Better represents work flow in continuous
  operations

9
Precedence Diagram Method

• Disadvantages
• Need to use finish to start relationships
• Harder to update and manage due to reduced
  network detail

10
Precedence Diagram Method

• Activity Lead Lag
• Lag time that a following activity is delayed
  from the start of the previous activity
• Lead time that an activity precedes the start
  or finish of the next activity

11
Precedence Diagram Method

• PDM Relationships
• Finish to Start
• Like AON when no lag
• Start to Start
• Gives a time between the current activity start
  and when next activity can start
• Finish to Finish
• Gives a time between the current activity finish
  and when next activity can finish

12
Precedence Diagram Method

• Calculation Assumption
• Once work starts it runs until complete
• Activities are scheduled based on their duration
• Work is not interrupted or stretched

13
Precedence Diagram Method

• Controlling Relationships
• Forward pass
• Relationship that results in latest early finish
  time
• Backwards pass
• Relationship that results in earliest late start
  time

14
Precedence Diagram Method

• Forward pass
• Calculates the earliest time each activity in
  network can start and finish
• Minimum project duration
• Backwards pass
• Calculate the latest time an activity can start
  and finish