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How to schedule a resource to switch from a job to another

12 replies [Last post]
Ahmad AbdRabou
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Joined: 10 Jun 2015
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Hello,

I'm schedulling an engineering job, MEP.

the plan for mechanical as follows:

there are 3 desginers, each will take a division - pluming 1 engineer, HVAC 1 engineer, and FF 1 engineer.

each have a drawing list with assigned hours for each drawing, and WBS is agreed.

FF desginer will be the first to finish, so, I want him to support pluming, but only after he finishes his given task.

then when both FF and pluming finish, I want them to support HVAC.

How can I do that on P6.

Thanks in advance.

Replies

Rafael Davila
User offline. Last seen 5 hours 39 min ago. Offline
Joined: 1 Mar 2004
Posts: 5229

Hassan,

This will delay the start of activity on Building 2 until activity on Building 1 finishes when the plan is for both activities to start at the same time and when the shorter activity finishes its team will move to assist the other team.  In addition because work on Building 1 might be delayed a good model shall delay the movement of Group 1 until activity on Building 1 finishes and adjust the duration of activity on Building 2 accordingly, in this case considering the simple case where both resources have same production rate.  Schedules are dynamic, good resource models shall be dynamic.

Best Regards,

Rafael

Hassan Thakur
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Joined: 21 Feb 2015
Posts: 2

Dear Ahmed:

Simply stated you have two activities with

Building 2Building 1
5000 sqm1000 sqm

Assign

Group 2 and

Group 1

Assign Group 1 Only
Set Activity Leveling Priority : NormalSet Activity Leveling Priority: High 
  

Now when you schedule your programme with resource leveling, everything should fall in place. i.e. Group 1 after finishing their work should go to Building 2 work.

 

Hope this helps.

Rafael Davila
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Joined: 1 Mar 2004
Posts: 5229

- where to start allocating the support group?

You shall start allocating the support group as soon as it finishes on activity 1.  The model shall adjust how much work is to be performed on the second activity based on total allocation of production resources. 

As per your request the scenario with both activities starting at the same time and resources having same production rate is as follows.

Cladding05 photo Cladding 05_zpsuxd6qwvf.jpg

We are talking about two different buildings and therefore it makes no sense to fix the start of cladding activities at different buildings. If start of second activity is delayed the distribution will be different, adjusting this manually every time you re-schedule and start of activities relative to each other varies.  This cannot be done automatically if using separate activities each with a fixed duration/volume and therefore is a poor solution.

If Activity on Building 2 is delayed as shown in the following figure the most efficient work distribution varies.

Cladding06 photo Cladding 06_zpskfrsqjac.jpg

If start of Cladding on Building 2 is delayed further at some point Crew 1 will be able to start on the activity at the beginning and the work distribution as well as the required activity duration to perform the same amount of work will change.

Cladding07 photo Cladding07_zpsbuyxzlqz.jpg

When you have hundreds of activities competing for the same resources manual methods are not a good idea.

Raymund de Laza
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Joined: 22 Nov 2009
Posts: 762

Create an Activity that represent 1000 SQM in each building for a certain duration. Assign the Crew in each activity.

Both Crew will start at the same time and finish the task at the same time.

Then the activity for the remaining 4000 SQM will be done together by both crews. Either you breakdown the 4000SQM Activity by so many activities, both crew shall be assigned to those activities.

 

Hope this will help.

Raymund de Laza
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Joined: 22 Nov 2009
Posts: 762

  

Ahmad AbdRabou
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Joined: 10 Jun 2015
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Alright Rafael, so much effort you do and I appreciate it, so lets focus on the cladding job senario No. 1 ( cause this is exactly the case ) with the following information,

* some information will be repeated from last post, just to keep the sharp focus, so bare with me.

- 2 buildings need cladding, Building 1 is 1000 sqm, Building 2 is 5000 sqm

- Both buildings must start at the same time.

- Cladding work in one building is not a one activity, it is a series of activities with complicated relationships (don't know if it makes a differece in the main princible of solving this problem)- 2 cladding groups, each will go for a building

- Both cladding groups have the same manpower quantity, productivity, working time (ex. 8:00AM to 4:00PM)

- The finishing time of building No. 1 (1000 SQM) is upto schedulling process, I don't know the excat date, it's just the equation of building quantity / group productivity  -  This is where the problem starts

from what I see, there are the following problems,

- where to start allocating the support group?

- budget unit for the activity changes whenever I add or remove a resource (I'm using Fixed United activity type)

please, review with me how much did you realise of this problem, before you start giving solutions

Regards,

A. AbdRabou. 

Rafael Davila
User offline. Last seen 5 hours 39 min ago. Offline
Joined: 1 Mar 2004
Posts: 5229

If the crews are allowed to work as separate teams then shift work must be used, especially if the work hours of the crews are different.  The following model allows for different crews working at different hours [Scenario 01], if you require for them to work at same work hours then they would be able to work together only 4 hours per day [Scenario 02]. In both cases it was not necessary to use variable quantity.

Scenario 01:

Cladding05 photo Cladding05_zpsnr4ezarw.jpg

Scenario 02:

Cladding06 photo Cladding06_zpsldagdo9a.jpg

For design work if support role means they must work together then the resources must be assigned to the same team.

These resource planning scenarios are very common and you must know how to deal with them, otherwise people at the field will throw away the schedule and do their best by themselves.

Rafael Davila
User offline. Last seen 5 hours 39 min ago. Offline
Joined: 1 Mar 2004
Posts: 5229

If the crews are allowed to work as separate teams then shift work must be used, especially if the work hours of the crews are different.

The following model allows for different crews working at different hours, if you require for them to work at same work hours then they would be able to work together only 4 hours per day. In this case it was not necessary to use variable quantity. This would be my preferred way to model independent crews no matter if working on the same work hours.  On the other hand for design work if support role means they must work together then the resources must be assigned to the same team.

Cladding05 photo Cladding05_zpsnr4ezarw.jpg

Rafael Davila
User offline. Last seen 5 hours 39 min ago. Offline
Joined: 1 Mar 2004
Posts: 5229

In such case you need to consider volume of work, resource production rates and variable quantity.

Scenario 01- Both activities starting at the same time.  Only one crew can work on Building 1 while Building 2 can accomodate 2 crews.

Cladding01 photo Cloadding01_zps2khwddvm.jpg

Scenario 02 - Similar but activities linked one after another. This increases project duration while each individual activity durations are reduced.

Cladding02 photo Cladding02_zpsgw8aczl9.jpg

Scenario 02 Cladding Crews production/day.

Clad photo Cladding02B_zpsbeuchquy.jpg

Keep in mind that the use of hammocks or level of effort will not level the resources, you must avoid it.

I hope this can give you a clue, such everyday resource planning issues are easy to schedule.

Ahmad AbdRabou
User offline. Last seen 1 year 39 weeks ago. Offline
Joined: 10 Jun 2015
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thanks for your reply, I appreciate,

still can't figure this out, I need an example for primavera

I'll explain my problem with different example,

suppose there is a cladding job for 2 buildings, the first is 1000 sqm, and the second is 5000 sqm

and there are 2 groups of cladding, each group will start working in a building, and both will start in the same time.

so far, there's no problem in primavera, but then....

when the first building finish, the free cladding group will go to support the other one till the second building is finished as well.

that's what I don't know how to do in primavera.

thanks again

Rafael Davila
User offline. Last seen 5 hours 39 min ago. Offline
Joined: 1 Mar 2004
Posts: 5229

It is not uncommon for our designers to have several jobs at the same time and share designers among the jobs, in such case you shall use variable quantity and workloads. Different to the previous example where only variable quantity was used and workload fixed at 100%.

MEP04 photo MEP04_zpso71ebn12.jpg

In the case of more than two jobs [say four] to be worked by same designer it might not be a good idea for the designer to work 2 hours per day on each job but to work 4 hours per day on two jobs 2 days/week and 3 days/week on the other two, for this use of shift calendars for the activities will do it.  Another option is; assign 2 days for 2 specific job, an intermediate day to buffer activity, and 2 days for the remaining two and let designers work during intermediate/buffer day on any of the four jobs as need be. In some weeks the intermediate day shall be used to make up for holidays.

The schedules are simple but the assignment rules you must figure out.

Good Luck.

Rafael Davila
User offline. Last seen 5 hours 39 min ago. Offline
Joined: 1 Mar 2004
Posts: 5229

It looks like a simple case of variable quantity resource loading, a very common scenario.

It is just a matter of figuring it out with your software as this is a common resource assignment scenario.

First create your activities/tasks and logic then resource load and level. I am not a designer so you might need to add some links.

To fine tune the schedule I would include in the model that for resources doing some support work their productivity would be lower than main designer and this would have a dynamic impact on activity duration.  But first you must start with the very simple things.

MEP02 photo MEP02_zpso5ftzp18.jpg

 photo MEP03_zpsqqbx09we.jpg