Task activities and hammock activities

Hello,

I found one article explained clearly for Hammock

1. P3 calculates the duration of a hammock activity and graphically presents it on the layout
based on the early dates only.
2. For a hammock activity with no progress, P3 calculates a hammock’s duration by the
difference from the earliest early start date of the its predecessor activities to the latest early
finish date of its successor activities. Therefore it has no fixed duration. P3 calculates the
original and remaining durations automatically based on the following formula:
a. Original Duration = (Early Finish Date – Early Start Date)
b. Remaining Duration = Original Duration
3. A hammock should have at least one predecessor and one successor. A hammock without
predecessor starts on the data date, and that a hammock without successor ends on the
project completion date.
4. For a hammock activity in progress, a hammock activity bar starts on the actual date, and
P3 calculates the original and remaining durations, and percent complete automatically
based on the following formula:
a. Remaining Duration = (Early Finish Date – Data Date)
b. Original Duration = (Data Date – Actual Start) + Remaining Duration
c. Percent Complete = (Original Duration – Remaining Duration) / Original Duration
5. A hammock activity can’t drive (push out) any task activities. I often call its behavior like a
“Rubber Band” as it is stretched or compressed according to its successor and predecessor,
not the other way around.
6. If you unlink the remaining duration and schedule percent complete in the Autocost Rules
window, you can manually enter the percent complete for a hammock activity. However,
you absolutely can’t manually enter the original and remaining durations. P3 will overwrite
your inputs.
7. An asterisk mark (*) will always be shown right next to the original and remaining durations
of a hammock activity to denote that the durations are automatically calculated by P3.

Or, to keep it simple.

A hammock summarises task activities (using the criteria provided by Praves)

Hello Paul and Praves

Thanks a lot.

Regards.

Marcio Eduardo.

Hello all.

Read this other response.

From Primavera:

Define a task activity. P3 schedules a task activity according to
the base calendar assigned to the activity. Designate an
activity as a task activity if you aren’t assigning resources to the
activity, or if the assigned resources should be scheduled
according to the activity’s base calendar; rather than each resource
calendar.
For example, several activities must be done in the week before a new
radio station begins broadcasting. It doesn’t matter
whether the resources are available earlier than that week, or
whether they will otherwise be scheduled for time off during
that week--these activities must be scheduled during a specific
timeperiod, and their scheduling controls the scheduling of
their resources.

Define a hammock activity. Use hammocks to monitor the elapsed
beginning-to-end duration of a group of activities. A
hammock duration is the number of days between the beginning of the
first activity and the end of the last one in the
group--not the sum of the activities’ durations. If several hammocked
activities overlap, the hammock’s duration will be smaller
than the combined durations; if large gaps exist between the
activities in the hammock, its duration may be longer.

To set up a hammock activity

1 Display the Predecessors form for the hammock activity.
Define the hammock’s predecessors. Specify a start to start
relationship and zero lag for all predecessors to the hammock.
2 Display the Successors form for the hammock activity. Specify
a finish to finish relationship and zero lag for all
successors to the hammock.
3 After you establish the beginning and ending points of the
hammock, calculate the schedule.

Regards.

Marcio Eduardo
Rio de Janeiro - Brazil