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Scheduling Lane Closures for Multiple Operations

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Greg Paulson
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Hello,

I am putting together a short term schedule with multiple operations on a highway that requires traffic closures each night.   Each activity is specific in which direction traffic needs to be closed.

If it were only one operation, I would consider assigning the lane closures as resources.  (i.e. a northbound closure for road replacement, striping, etc. in that direction, and one for the southbound direction.)  Then I could print a resource usage profile to show what closure we need to plan for.

For multiple concurrent operations, I can't wrap my head around how to assign a resource that would allow me to level the schedule and allow for only one traffic closure direction at a time.  Any ideas?

Thanks,

Greg

Replies

Anoon Iimos
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Yes Rafael, that's should be the exact sign: "Sorry for any Inconvenience", but some contractors don't even bother to put any sign (as a show of courtesy). Instead, they put more aggressive or even political signs like: "Government Project. Do not Delay or Interrupt. Or This Project is Thru the Efforts of blah blah (politician). And that's it! That will solve any problem for road closures here...LOL. Unfortunately, that's what I know from real life experience. So again, "Sorry for any Inconvenience"
Rafael Davila
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Anoon what you are saying makes no sense at all.  Your prior hijacking of one of my discussions and now your childish interruption of this discussion is annoying.

Anoon01

Anoon02

Anoon Iimos
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In the place where I live, traffic and road closures due to construction or whatever, were normal day to day struggle for us. Here even a good road that has no damage will be closed from time to time due to maintenance of water lines buried in the middle of it or even change it with a new pavement as perhaps some local politicians have found a way to make profits out of the project. Having said that, it is my opinion that road closures and related activities are constraints by themselves. So you can always do them once you got Time and resources and you were allowed to do so, whether or not it's a northbound or southbound lane. Once a certain lane is closed (even if it's just a small segment), then of course it will not be opened until again ready for traffic use. So why worry with resource leveling when in fact you won't be needing it?
Rafael Davila
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Closures can be sequenced in any order, ideally following some prioritization but as soon as there is a change in plans such as a few activities must be delayed due to external date constraint the fixing of artificial relationships can be tricky and error prone even for such simple schedule.  

Activity-Gantt-Resources-F-202-Lane-Closurespng-Page1

I suspect Greg have been using artificial “soft-links” and found it a nightmare to make such frequent adjustments therefore he is looking for a better way. What Vladimir suggests looks practical if using P6.

Adding the paving activities to be scheduled a maximum of five closure sections Sunday during daytime if using "soft-links" become further complicated, any small change will impact all resource dependencies, easy if using correct resource model that do not depends on such annoying links.  

Activity-Gantt-Resources-F-203-Lane-Closures

As things change further delays might happen, no need to change schedule logic if using resource leveling.

If you want to change prioritization just change it at lane Closing phase level, reschedule at a single click and done.

Currently a similar job is being done by municipality close to home on a very busy road.  During weekdays at night the scarification or cold milling of pavement sections then paving on Sundays.  As the exposed base layer is black base there are no issues with leaving it exposed for several days.  I noticed they are moving from KM0 to KM3 on all lanes, so this is their prioritization.  I also noticed some segments were skipped to be worked a bit latter, I suspect not everithing goes always as planned.

Zoltan Palffy
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I am not sure I understand the question why wouldnt a simple FS relationship be sufficient ?

Northbound work with a successor of Southboud work ?

I must be missing something here 

Rafael Davila
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I suspect Vladimir suggestion can make it with P6. If NB closures are ~50% of all closures while the remaining 50% is SB, I suggest alternating days for closure direction and using phase priorities to keep it close to a desired work order if there is no median barrier.  If some activities must be delayed due to some date constraints I expect everything will be scheduled as expected per this model.

If there is a median barrier I expect preferred order of execution to be different.  I do not recall P6 being able to control availability of resources through activities but using strict calendar.  If so this can be a huge problem.

If using spatial resource model the schedule should be closer to the desired work order when priorities do not follow a fixed closure pattern.

Activity-Gantt-Resources-F-202-Lane-Closurespng-Page1

It can also be modeled using resource production and consumption following way:

1) Create resource Northbound and assign it to all northbound activities and create resource Southbound and assign it to all southbound activities together with other resources,

2) Set that there are 100 available Nothbound resources at times when northbound part is permitted for work and 0 at other days, the same with Southbound resources.

3) Level resources.

I did not try this in P6 but hope that it is able to model this simple scenario.

 

Raymund de Laza
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There are 3 most common Resources that comprises an Activity.

1. Material (Consumable and Non Consumables)

2. Manpower (Labor)

3. Equipment or Tools.

As I understand from Greg post, there is one Crew (Manpower or Labor) that is available to execute the multiple activities.

It is needed to assign the crew in the multiple Activities then level the resources and it will results as those activities are executed one after the other.

To obtain the result, just establish the max number of Crew to 1 Unit per time. Then perform the resource levelling.

 

Im hoiping this will help.

Rafael Davila
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Steven,

We do not use any Spatial Resource option/functionality such as Aurora Scheduling does, but model them through consumable resources.  

I am exposing how Spatial Resources can be modeled using Consumable Resources via a simple four steps methodology. 

  • Do you mean P6 cannot level Consumable Resources?

Resource types: Renewable and consumable resources

  • 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. As an example, skilled laborers are available to work each day on a project, although their availability is limited each day and may vary over time due to absence, sickness, vacations, etc.. Consequently, there is no general constraint placed on the number of days skilled labor may be used but instead they are renewed each period of the project.
  • Consumable resources (or non-renewable) are not constrained on a periodic basis but rather have a limited consumption availability for the entire project. Typical examples are money, raw materials and energy. Usually, the overall project costs are limited and pre-defined in a total contract price. Their consumption is not renewed as is the case with renewable resources; but instead, these resources are consumed when used.
  • 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. Flying forms for elevated slabs is an example of Spatial Resources that occurs very frequently in construction schedules.
  • Please note "space" and "spatial" resources are different, space is a renewable resource while spatial resource is a different type.  They all happen very frequently, a schedule to be viable must take in consideration all resource constraints.

Best Regards,

Rafael

Steven Auld
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Rafael,

Given that this was posted in the Primavera P6 Forum, it is unlikely that Greg is using Spider Project - so would not have the "Spatial Resource" Option available to use.

Greg, Version 3 in Rafael's post is the equivalent of what I described in my previous post.

If there is a large number of activities that need to be assigned as a successor to the Lane Closure Start or End Milestone, on the Relationships Tab (or Predecessor Tab depending on your preference), Select the first activity in the Activity Layout then "Assign" in the Predecessor Relationship - this will open the "Assign Predecessors" box - search for the required Milestone in this list, but do not yet assign the value.

In the Activity Window, now select all the activities that require the specific Lane Closure then assign the Predecessor to all activities at once.

The links between the lane closures only require 1 link between the finish of the First Lane Closure Milestone & the Start of the Next. If you need to change the sequence, just delete this one relationship then reassign the Lane Closure Milestone Relationships in the Required Sequence.

Hope this helps.

Steven

 

Rafael Davila
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Please take a look at the following figures [just click] for a view on how we handle spatial resources and why using common renewable resources will not make it.  The option to create artificial links to manually level resources is error prone and requires much manual adjustments upon every update.  The option to use spatial resources do not have such problems.

There are 3 resources A available. There are 3 resources B available. Road closure activities groups are not hard linked among themselves.

Version 1: Considering renewable resource A and B but no spatial resource. Renewable resources are leveled. Spatial requirement for a single closure at a given time is broken.

Lane-Closurespng-Page3

Version 2: Considering renewable resource A and B and a single spatial resource. Renewable as well as spatial resources are leveled. Spatial requirement for a single closure at a given time is satisfied. As always use phase priorities to keep some control on the leveling.

Lane-Closurespng-Page4

Version 3: Considering renewable resource A and B but no spatial resource, artificial or “soft links” are added to manually solve the spatial constraint. For such simple schedule manually leveling of spatial resource looks viable at first glance. As more activities are added it becomes harder to add the appropriate links, as things do not move as desired and a change in sequence is needed because some closure must be delayed the manual adjustment in sequence can become quite complex while if using spatial resource a single date constraint will take care of everything. Do not ever think about manually leveling such/similar schedule if assignments or activity relationships are a bit more complex.

Lane-Closurespng-Page5

A simple change such as resource demand varies from different groups of activities and a few non road closure activities sharing same resources are added can complicate things. Not many activities, imagine if just 60 activities, insane to adjust manually as things change and whatever artificial or "soft links" you created no longer makes sense. 

Activity-Gantt-Resources-FB-2-Lane-Closurespng-Page1

Spatial-Resources-F2

If no artificial "soft-links" and no spatial resources modeled the leveling might yield wild results.

Lane-Closurespng-Page1

Using soft logic is not a practical approach when there are many such links subject to frequent "soft link" changes as it happens in most resource loaded schedules updates.

Good Luck.

Steven Auld
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Greg,

Not sure why you are looking to add this as a resource.

I would have thought that the actual lane closure would be an activity in itself, as it would require something to be done to enable the work to proceed safely.

I would add a start milestone for each lane closure then link the activities that require this lane to be closed to this activity.

I would then add a finish milestone after completion of the works to the last activity to be completed that requires this lane to be closed.

On the completion of the 1st Lane closure, link the 2nd lane closure to the end of the 1st lane closure.

Use the calendars to ensure that work is only scheduled for the required period during the night.

The logic between the milestone completion should then drive the schedule accordingly if using resource levelling (or scheduling).

This is on the assumption that the lanes will only be closed in one direction / section at a time.

<> Northbound Closure (Milestone)

-- Road Replacement

-- Striping

-- etc

<> Northbound Available

> Finish to Start Link <

<> Southbound Closure

-- Road Replacement

-- Striping

-- etc

<> Southbound Available

Anoon Iimos
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TIME is the only definite unit of measure that makes matters or things exists. Space and all other units are variable. Speed or velocity makes matters more complicated. As speed increases, time correspondingly reduces, and so as the existence of a certain matter or activity. Meaning, if a certain activity goes on a tremendous speed, then it may become literally invisible or you might think that it doesn't exist (Can you see a fired bullet?). Scheduling always refer to Time. If you got Time, then for sure you can make other matters exist. Hope this helps.
Rafael Davila
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Greg,

I do  not use P6 but Spider Project so I do not know how P6 deals with Spatial Resources.  No matter what the modeling need is the same, cannot be modeled as if traditional renewable resources.

The following presentation illustrates how we model spatial resources, it is a simple four step procedure, please take a look at slide six. 

If I got it right:

  • You will need a single spatial resource to allow concurrent work on only one side of the road at any given time. 
  • I understand the different activities that make up a set of concurrent work for actual lane closure have their need for traditional renewable resources, the most common type. 
  • The spatial resource once released will be available for other set of concurrent work.
  • What next set is to be selected by the resource leveling algorithm must be considering the availability of the other renewable resources while looking to optimize project duration.
  • This particular scenario looks so simple that manual leveling using what is known as "soft links" might be a viable option. Soft links meaning not true logic links but links to manually solve the resource leveling. 

Best Regards,

Rafael
Raymund de Laza
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Greg, Assign a max unit per time for each resource. Then perform resource levelling.
Greg Paulson
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Rafael, this is exactly what i need to do, thank you. Do you have any links to instruction on how to assign spatial resources?
Rafael Davila
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Consider modeling activities requiring a lane closing using "Spatial Resource".

http://www.pmknowledgecenter.com/node/104