Resource Dependent Activities – Duration Calculation

Duration Calculation for Resource Dependent Activities:

Generic queries before analyzing Resource Dependent activities

What does “Resource Dependent” Activity type in Primavera mean?

Ans: It schedules the activity based on “Resource calendars” assigned

Where can i use “Resource Dependent” Type?

Ans: Where my activity is entirely dependent on my resource list added or in other words if my “At completion rate” is decided by actual resource reporting then Resource dependent need to be used.

What will be the impact on my schedule when “Resource Dependent is used?

Ans: Depends what duration type is associated either “Fixed Units” or “Fixed units/Time”

Does “Resource Dependent” change my “Remaining duration” based on units update?

Ans: Yes, it changes.

Can i associate duration type others than “Fixed units” of “Fixed units/Time” to “Resource Depend Activity”.

Ans: No, if still the association happens,”Remaining rate” or “At completion” will be blank – will not recalculate.

Remaining Duration calculation with Resource Dependent

With Resource dependent activity type always the calculate the duration % or how Remaining duration is achieved is trickiest.

It is calculated based on Formula:

Remaining Duration = Remaining Units / Units Per time

Let’s analyze this with an example where for an activity with duration of 25 days there are multiple resources used. Each resource has individual budgeted Units/time, and has type as “Resource Dependent “– Fixed Units. Note in my case both activity calendar and resource calendar are same.

Now let’s start updating the actual units and see how remaining duration is changed each time when units is updated.

How has the 25 days on the remaining duration has changed to 8.33 days?

Ans:

For Scaling and Mucking resource with Budgeted Units “105” now we updated with “70” hence remaining is 35. Same logic is applied to all resources in the screen. Now based on formula

Remaining duration (RD) = Remaining Units / Units per Time => 30 /4.2 => 8.33 .

But think of this calculation is based on weighted logic:

RD for scaling and mucking = 8.33 days (from formula)

RD for Defuming = 2.5/0.5 =5 days

RD for Drilling = 2.5/2.7 = 0.87 days

From this logic it takes the activity needs 8.33 units to complete the task. The same logic is applied to all resources and computation is carried in same way.