Tips on using this forum..

(1) Explain your problem, don't simply post "This isn't working". What were you doing when you faced the problem? What have you tried to resolve - did you look for a solution using "Search" ? Has it happened just once or several times?

(2) It's also good to get feedback when a solution is found, return to the original post to explain how it was resolved so that more people can also use the results.

About Consumable Resources / Materials and Spatial Resources

9 replies [Last post]
Rafael Davila
User offline. Last seen 5 hours 18 min ago. Offline
Joined: 1 Mar 2004
Posts: 4780

The two most common categories of resources on CPM software are; renewable resources and consumable resources.

Renewable resources are renewed as soon as a particular activity using the resource ends.   Only the total resource use at every time instant is constrained. Typical examples are manpower, machines, tools, and equipment.

Consumable resources (or non-renewable) are not renewed on an activity basis but consumed when used.  Typical examples are money, raw materials and energy.  Usually, the overall project costs are limited and pre-defined in a total contract price.

When I started looking for Consumable Resources /Materials I could not see the potential applications other than some way to manage inventory of materials.  Unless you have issues with storage capacity then you might not feel the need to model your inventories within the CPM model. 

But the potential need for consumable/material resource functionality is there for other scenarios that cannot be modeled without consumable resources functionality.

Recently I was confronted with the issue of modeling form-work sets and found that the use of materials functionality is a perfect fit for cases when you have a need to keep reserved the form-work from the first moment an activity from the group starts until the finish of all activities from that group.  This is a different scenario to when form-work can be moved from activity to activity without the need to keep it reserved for a group of activities before it can be used by other activities or groups.

It also came to my mind it could be a perfect fit to control the start of an activity upon the start/finish of a certain number of activities within a group.  The use of regular resources along with resource production can be an alternative.

About space as a resource it comes to my mind that similar to form-work it can be modeled using either renewable resources or consumable resources depending on the particular scenario.

I would like to share with you all potential applications we can think of for consumable/material resources and ask you to provide your comments and suggestions; some sample job files will also be welcomed.

My share:  http://www.mediafire.com/?e0fr16edp8oklvl,gxbgdjzd6n6hq55

Best Regards,

Rafael

Replies

Rafael Davila
User offline. Last seen 5 hours 18 min ago. Offline
Joined: 1 Mar 2004
Posts: 4780

Vladimir,

Perhaps the Delay Reason could be used to transfer a multi-constrained schedule [resources/materials/financial/ and other constraints] to another software that lacks such functionality.

At the moment we can transfer Resource Dependencies as regular links but no equivalent exist for Material and Financial Constraints.  Even if such equivalent existed there is a possibility these could be Double Links, something not available in other software.  

Whenever an Activity is delayed because of Material or Financial Constraints these can be transferred as a start no earlier than constraint generated using a formula that looks at Delay Reason field. For clarity Delay Reason can be transferred via a user defined field.

Maybe the creation and transfer of such artificial constraints can be automated through the export function in the same way it can transfer Resource Dependencies. This without actually creating the artificial constraint in Spider Project.

I also would like Delay Reason field to be available on Resource and Material Gantt Diagrams, at the moment it is only available at Activity Gantt.

Best Regards,

Rafael

Rafael Davila
User offline. Last seen 5 hours 18 min ago. Offline
Joined: 1 Mar 2004
Posts: 4780

Vladimir,

Finding out that an activity was delayed because of a Material instead of a logic predecessor is unreliable when looking at Delay Reason field. The disclosed delay reason when due to a Material does not makes sense to me, especially when there is a logic predecessor disclosed as the delay reason when it was not the real delay reason but the lack of the Material.

In the following figure Activity B3 is delayed because of Material leveling, not because of Activity B4, this is confusing.

 photo QQ01_zpsd34ae569.jpg

Any of the following resource leveling options can be a delay reason, the software is smart enough to determine when to delay any activity because of any of them. The software knows it so well that always do it right.

 photo QQ00_zps8bdd859f.jpg

In addition to a particular resource leveling constraint an activity can be delayed because of a logic predecessor as well as because of date constraint.  To me this particular field "Delay Reason" was one of the most expected functionalities ever as it would be accurate and always would give me the reason why any activity have the start/finish date different than year 0. Usually most activities without predecessors are delayed because a Date Constraint equal to Project Start, so every activity have a Delay Reason.

I value so much the Delay Reason field that I would like it to be shown on the Activity Properties Dialog, perhaps under the Calculated Data tab.

Best regards,

Rafael

Rafael Davila
User offline. Last seen 5 hours 18 min ago. Offline
Joined: 1 Mar 2004
Posts: 4780
Vladimir,  The software works as expected in both cases the issue is on developing correct model for your particular needs. In the case of deliveries for different materials, in the case supplies (and materials) are specific, correct model would look as follows.  I combined materials A, B and C as if same material but one unit of each because if consumption is spread along the duration of an activity fractions of a single material would be installed on different activities. Looks similar but there is a slight difference on line 17.  photo JIT759_zps1ac541b2.jpg I am exploring use of Material Center leveling and so far so good, works as expected.

Material modeling is great for complex models, it can even be used for spatial resources of which I know almost nothing other than it is used on ship and airplane construction industries.  I believe I used the concept of spatial resources via Spider Materials functionality for the Form-work example. 

Best regard,

Rafael

Yes, in your case the schedule is as you posted because material supply is sufficient for executing two activities in parallel.

It is seen on Material Flow diagram below:

 photo Delivery4_zpsf3c0e365.jpg

You are right that before inserting the fragment material code shall be changed.

But if the same material can be used at different places then supplies shall be planned not for each place separately but for the whole project. In other case supplies (and materials) are specific.

Regards,

Vladimir

Rafael Davila
User offline. Last seen 5 hours 18 min ago. Offline
Joined: 1 Mar 2004
Posts: 4780

Vladimir,

Sorry, I should have posted the files. I can see two differences, the duration of delivery activity on phase 3 is 10 days and the duration of last activity on each phase is 36 days [though this is not relevant to the issue].

http://www.mediafire.com/download/v51tv8td1attnhq/RD023.001.sprj

The version using a different material for each phase is.

http://www.mediafire.com/download/4w3me4824jc2j2d/RD023.002.sprj

I could not get the Diagram you are displaying and suppose it is very informative. 

Best Regards,

Rafael

Rafael,

I could not repeat your example.

My result:

 photo Delivery3_zpsd959e465.jpg

Rafael Davila
User offline. Last seen 5 hours 18 min ago. Offline
Joined: 1 Mar 2004
Posts: 4780

Vladimir,

I modeled your suggestion and it seems you cannot copy phases without some adjustments. Note line 17 is wrong.

 photo 9-7-20139-45-54PM_zps07c8288c.jpg

The following figure shows the same after adjusting the schedule assigning a different material to each phase and it seems like it works as expectd. 

 photo 9-7-20139-46-29PM_zps69c5b246.jpg

Am I  right or wrong with my assesment?

Best Regards,

Rafael

Rafael Davila
User offline. Last seen 5 hours 18 min ago. Offline
Joined: 1 Mar 2004
Posts: 4780

This is a continuation for a discussion from the following link:

http://www.planningplanet.com/forums/oracle-primavera-pm6/549569/define-correct-relationship-between-activities

There we were discussing how to model close to just in time deliveries. The idea is to delay deliveries close to installation time but not as much as to consume all float with regard to installation. The model we are looking shall display correct late dates and correct float values for delivery activities.

The solution proposed by Vladimir is as follows and will be discussed here as to check float values [late bars] as well as how to copy and paste the procurement activities in a way the validity is maintained. 

 photo 9-7-20133-56-13PM_zps39b1abbc.jpg

Best Regards,

Rafael

Rafael Davila
User offline. Last seen 5 hours 18 min ago. Offline
Joined: 1 Mar 2004
Posts: 4780

 photo Materials06_zps4de31b43.jpg

Buildings C and E each requires two sets of flying forms the remaining will require a single set, 3 sets will be assembled.    

 photo materials09_zpsa6c48068.jpg

Note above that regular resource loading hammocks can be a trap in certain scenarios. Regular resource loading on individual activities or hammocks will not produce a safe model for this scenario.

http://www.mediafire.com/download/asj5awe6al7m08k/RD021.002.sprj

The above sample schedule was developed using regular resources with the purpose to illustrate it is a trap to use hammock as well as individual activities in lieu of material resources to model the use of form-work that must be reserved for a group of activities before being released for use by other activities.

 photo Consumables02_zpsb6aa3177.jpg

This one explains itself.  More complex scenarios are equally easy to set-up.