Leveling of Spatial Resources as if Renewable Resources will not do it :
Renewable resources are available on a period-by-period basis, i.e. the available amount is renewed from period to period (e.g. per hour, per day, ...). Only the total resource use at every time instant is constrained. Typical examples are manpower, machines, tools, equipment and space.
Spatial Resources are required by a group of activities, rather than a single activity as renewable resources. The spatial resource is occupied from the first moment an activity from the group starts until the finish of all activities from that group.
Modeling of the travelling scaffold system [a Spatial Resource] as if Renewable Resources will prevent for any/some activity to happen at the same time as required – “but several activities will be performed from the same "access" concurrently in the same location”.
Just take a look at the following sample schedule to see how distorted the results can be.
I do not use P6 but Spider Project, maybe you can follow what I did within my software and translate it into yours. We model Spatial Resources using Consumable Resources. Please take a look at the following presentation, it is a simple four steps process.
For strict logic sequence the following might be a way to do it, it looks like the approach you are suggesting, good for such simple scenario.
You can download from the following link a PDF showing a sample schedule of spatial resources, each job is independent of each other, their start is not related to any other. If you delay some job automatically other will take its place as long as there are enough spatial resources available. Making changes to such simple project as to level resources by adding/deleting activity links is difficult if you delay some activities and increase/decrease availability of spatial resources for different seasons.
I'm not familiar with how to assign a spatial resource in P6. Can you explain?
The work consists of 4 independent sequences: removing, priming, installing, then painting four separate girders. The contract requires that these activities not be combined and they will all be performed from the same scaffold concurrently. Each sequence has a different total duration. The scaffold will remain at a stationary location until all four sequences are complete.
My thought was to create a LOE activity for each scaffold position that has a SS pred with the removal activity for each girder, then a FF succ with the paint activity for each girder. Then I would assign the scaffold resource to that LOE activity.
A side benefit would be that a LOE filter would show a nice summary sequence for the scaffold.
This is the approach I am considering. I have a couple days to consider additional approaches you might have while I wait for the review to come back for my next round of revisions.
Only in special cases when your software cannot model spatial resources.
I do not like it because as soon as things change the true sequential order might change. Say for example you increase from one to two or more such resources at some point if schedule starts to lag, or if one segment is delayed and another segment becomes available earlier. In the first case simply increase the availability of the resource in the second case it is taken care automatically by the spatial resource model.
Spatial resources are required by a group of activities, rather than a single activity as renewable resources. The spatial resource is occupied from the first moment an activity from the group starts until the finish of all activities from that group. Examples are dry docks in a ship yard or a freezing machine in the Westerscheldetunnel.
Thank you for the insight! The concept of a "spatial" resource was what I was grappling with.
I'm not clear as to how I will assign one in P6, but I am going to try to use a Level of Effort to group each sequence and assign the scaffolding resource to the Level of Effort activity.
This is my interpretation of:
If the activities happen in strict sequence then you might create a hammock for every group of activities and resource load the hammock. A workaround that might do the trick in some cases.
It looks like your resources are Spatial Resources that must be leveled. So common in my work (Building Construction) that it happens in almost every one of my jobs.
In cases where the sequence is not strict logic such as the case in which you have many buildings that can be worked at the same time or with some overlapping there is no other option than to model the spatial resource as such.
If the activities happen in strict sequence then you might create a hammock for every group of activities and resource load the hammock. A workaround that might do the trick in some cases.
Partial Workloads either fixed/variable is not what happens in this scenario. We use partial workloads everyday for shared resources such as a crane. A resource in high demand that must be leveled so that it is not scheduled to work on more activities it can handle every day.
if you are limited by this 1 piece of scaffolding then the 8 activites need to be FS and CAN NOT be done concurrently. This would be a equipment constraint.
I agree with your definition of access. However, when creating the baseline schedule, "Access" was a generic term for the equipment that would provide access to the work area. At the time when the baseline was created (I inherited this schedule and am not its original creator), the equipment had not been designed and an equipment resource "access" was created.
The system that was designed is a 100 ft long scaffold that is dismantled and moved to the next location after all work is done at that 100 ft section.
Now I have a situation where a single piece of equipment has been assigned to multiple activities. If I assign it to all 8 activities, I am overallocating the single piece of equipment as a resource and the activities will shift when I level resources.
Would the solution be to allow an unlimited number of hours for this equipment resource and essentially make the leveling useless?
Leveling of Spatial Resources
Leveling of Spatial Resources as if Renewable Resources will not do it :
Sample Schedule – Leveling for number of beds in offshore work as Spatial Resource
Sample Schedule – Leveling for number of beds in offshore work as Renewable Resource yields weird results.
Levelling of Resources will
Levelling of Resources will do.
First set the Max Units / Time as 1 scaffold per day in the resource details under Units & Prices Tab.
Then, Assign the Resource to all Activites.
Set Priority Levels for every activity.
In the Levelling of Resource Pane, set Levelling Priorities, Select which Resource to Level then Level.
Hope this will Help.
I do not use P6 but Spider
I do not use P6 but Spider Project, maybe you can follow what I did within my software and translate it into yours. We model Spatial Resources using Consumable Resources. Please take a look at the following presentation, it is a simple four steps process.
You can download from the following link a PDF showing a sample schedule of spatial resources, each job is independent of each other, their start is not related to any other. If you delay some job automatically other will take its place as long as there are enough spatial resources available. Making changes to such simple project as to level resources by adding/deleting activity links is difficult if you delay some activities and increase/decrease availability of spatial resources for different seasons.
I'm not familiar with how to
I'm not familiar with how to assign a spatial resource in P6. Can you explain?
The work consists of 4 independent sequences: removing, priming, installing, then painting four separate girders. The contract requires that these activities not be combined and they will all be performed from the same scaffold concurrently. Each sequence has a different total duration. The scaffold will remain at a stationary location until all four sequences are complete.
My thought was to create a LOE activity for each scaffold position that has a SS pred with the removal activity for each girder, then a FF succ with the paint activity for each girder. Then I would assign the scaffold resource to that LOE activity.
A side benefit would be that a LOE filter would show a nice summary sequence for the scaffold.
This is the approach I am considering. I have a couple days to consider additional approaches you might have while I wait for the review to come back for my next round of revisions.
Thanks for your continued interest in my issue!
Does that seem like a
Does that seem like a reasonable approach?
From - Resource types: Renewable and consumable resources
Spatial resources are required by a group of activities, rather than a single activity as renewable resources. The spatial resource is occupied from the first moment an activity from the group starts until the finish of all activities from that group. Examples are dry docks in a ship yard or a freezing machine in the Westerscheldetunnel.
Thank you for the insight!
Thank you for the insight! The concept of a "spatial" resource was what I was grappling with.
I'm not clear as to how I will assign one in P6, but I am going to try to use a Level of Effort to group each sequence and assign the scaffolding resource to the Level of Effort activity.
This is my interpretation of:
Does that seem like a reasonable approach?
Thanks again,
Greg
It looks like your resources
It looks like your resources are Spatial Resources that must be leveled. So common in my work (Building Construction) that it happens in almost every one of my jobs.
if you are limited by this 1
if you are limited by this 1 piece of scaffolding then the 8 activites need to be FS and CAN NOT be done concurrently. This would be a equipment constraint.
I agree with your definition
I agree with your definition of access. However, when creating the baseline schedule, "Access" was a generic term for the equipment that would provide access to the work area. At the time when the baseline was created (I inherited this schedule and am not its original creator), the equipment had not been designed and an equipment resource "access" was created.
The system that was designed is a 100 ft long scaffold that is dismantled and moved to the next location after all work is done at that 100 ft section.
Now I have a situation where a single piece of equipment has been assigned to multiple activities. If I assign it to all 8 activities, I am overallocating the single piece of equipment as a resource and the activities will shift when I level resources.
Would the solution be to allow an unlimited number of hours for this equipment resource and essentially make the leveling useless?
I do not undersatnd the
I do not undersatnd the "access" resource
access usually means having the ability to get into a certain location
Set up a milestone for access then add the 8 activities as successors to the access milestone
add an equipment resource for the traveling scaffolding and assign it to the 8 activities