Precedence Diagram and Activity Duration Lecture Notes

Flashcards covering vocabulary related to precedence diagrams, linking relationships, and productivity calculation in construction management.

Precedence Diagram Nodes

Represent activities and may be drawn in any shape desired.

Activity Links

Lines used to represent the dependencies between activities in a precedence diagram.

Event / Milestone

A point in time without time duration, represented in precedence diagrams using activity notation with $0$ duration.

Dummy Activities

Activities that are required in arrow diagrams (A.D.) but are not required in precedence diagrams (P.D.).

Finish-to-Start (FTS)

A linking relationship where the finish of the activity determines the start of the successor.

Start-to-Start (STS)

A linking relationship where the start of the activity determines the start of the successor.

Finish-to-Finish (FTF)

A linking relationship where the finish of the predecessor determines the finish of the successor.

Start-to-Finish (STF)

A linking relationship where the start of the predecessor determines the finish of the successor.

Lag time

The time that follows an activity or is delayed from the start or finish of its predecessor.

Lead time

The time that precedes the start or finish of an activity.

Duration

Determined by the production rate or the productivity rate of a crew or a sub that performs the task.

Labor Productivity Rate

The number of work hours for a specific crew to place or install one unit of a particular item of construction.

RS Means

A specific source of productivity rate information cited for construction management.

Productivity Factor

A factor used to compensate for the difference between a project under planning and a "standard project."

Adjusted Duration

Calculated as $\text{Duration (or workhours)} \times \text{Productivity factor}$.