CECONMA LQ1 Flashcards
Breakdown of the project into elements that
are appropriate for time control.
Project Planning
Involves the concept of an objective or
project, and a scope of work defining the
work product or deliverable
Project Planning
Determining the resources and Forming of Organization
Project Planning
Parts of planning a project
- Review Historical Data
- Review Contract
- Review Drawings and Specs
- Communicate
Tips in activity list development
- Brainstorming
- Make a large list first, then select
- Use all sources of information
- Do a preliminary list, then refine
Things to consider in a project
- Work Breakdown Structure
- Work Packages
Considerations in a WBS
- Methods used to place work.
- Skills needed for the work.
- Craft workers involved.
- Critical resources (e.g., cranes, crews, etc.)
- Administrative actions that require time
- Deliveries or approvals that must be considered
- Special activities tied to the physical properties of the materials or
procedures required
refer to the work elements that appear in the schedule in their expected sequence or logical order
Activity
Considerations for Project Scheduling
- Determine Project Completion Time
- Determine Critical Activities
- Identify which activities can be delayed
- Use as a tool to manage a project
Steps required to develop a project schedule
(BEEFLR)
* Breaking
* Estimating
* Establishing
* Finding
* Looking
* Reviewing
Factors affecting activity durations
- Nature of work
- Quantities of work
- Technique used
- Resources used
- Working hours needed
Rules for estimating durations
- Assume each activity will be done normally
- Evaluate each activity independently
- Use consistent time units
- Keep good records as the schedule is developed
representation of a project
work item or activity as a time
scaled bar whose length
represents the planned
duration of the activity
Bar Charts
a graphical tool that shows a
project’s activities as rectangles
or circles joined by arrows
indicating their mutual
dependency or relationship.
Activity Precedence Diagrams
graphical representation of an activity
Arrow
Beginning or end of each arrow
Commonly called “events”
Nodes
Head of the event
j event
Tail of the event
i event
2 Basic Logic Patterns
- Activity on Arrow
- Activity on Node
Fictitious activity that has
no time duration and
requires no resource
utilization.
Dummy Activity
Has no fictitious or dummy activities
Activity on Node
Longest path on a network
Critical Path
Parts of a Critical Path Analysis
- Earliest (ES) & latest (LS) start
- Earliest (EF) & latest (LF) finish
- Float (F): Allowable delay
The length of time an activity can be delayed without delaying
the entire project.
Float
Activities with zero float
Critical Activities
What is PERT
Program Evaluation and Review Technique
An event-oriented network analysis technique that is used to estimate a project’s duration when individual activity duration estimates are highly uncertain.
PERT
Difference between PERT and CPM
PERT - probabilistic
CPM - deterministic
3 durations in PERT
Optimistic - a
Most likely - m
Worst - b
Assumptions in PERT
- Activity is assumed to have duration times that are randomly distributed. Activity durations are assumed to occur naturally.
- Variation in an activity duration should be the natural result of a fixed method of performance.
- Activity duration distributions must be the natural result of the
application of a fixed set of resources. - There are three estimated times of completion which can be estimated for each activity.
Sum of the “expected” duration variances along the critical path
Project Variance
Sum of “expected” duration along the critical path
Project Mean (Expected) Time
It is a user-defined amount; that is, we provide it along with other durations
(optimistic and pessimistic) in the equation so that we can calculate the expected duration and the standard deviation.
Most likely Duration
the amount of time that we expect the project or path duration to take, considering the different durations (optimistic and pessimistic), their values, and their weights.
Expected Duration
means shortening the normal duration of the project schedule without reducing the original scope of work
Project Acceleration/Schedule Crashing/Project Compression
Why accelerate a project?
- Contractor’s “normal” calculated finish date in the planned schedule does not meet the imposed finish date in the contract.
- After starting construction and completing a certain percentage of the project, the contractor realizes that the project is behind schedule.
- Contractor may have a contractual monetary incentive to finish ahead of schedule.
- If the economy is doing well, finishing early means, to the contractor, starting another project earlier and, thus, making more profit.
- Accelerating a project may prove profitable to the contractor.
an analysis and comparison of cost versus value of building materials, equipment, and systems
Value Engineering
the optimum use of construction knowledge and experience in planning, design, procurement, and field operations to achieve overall project objectives
Constructability
Factors to consider in crashing
The amount by which an activity is crashed is, in fact, permissible.
Taken together, the shortened activity durations will enable one tofinish the project by the due date.
The total cost of crashing is as small as possible.
The activity or activities must be critical and must shorten all existingcritical paths.
general overhead that the construction head office must carry
Indirect Cost
cost that occurs on each activity in the project network
Direct Cost
Types of Indirect Cost
Project Overhead/Job Overhead
General Overhead
Profit
Contingency Fees
the amount of time required to finish the project under
ordinary circumstances without any
deliberate acceleration or deceleration.
Normal Duration
cost of a project that is performed within the normal
duration. These definitions also apply to individual activities.
Normal Cost
Issues to Consider when accelerating a project
- Choosing the contract type and delivery method
- Effect of acceleration on cash flow
- Frequent updating and accuracy of information
- Space, logistics for safe and efficient operations; shift turnover or loss of time and productivity; fatigue, long-term exhaustion and stress on staff and laborers; equipment maintenance, managing subcontractors
- Procurement of resources
- Government permits and regulations
- What to do with extra staff, workers and, equipment after completion
