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Agree on Definition of EoT Methods

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Mike Testro
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Hello Everyone.

This is a serious research request.

PP members are talking about Time Impact Analysis - Impacted as Planned etc and there are different interpretations as to what the methods mean in various locations.

Let us try to simplify & standardise the definitions.

Scenario 1.
When work is in progress and events are impacted to show the likely effect on the completion date.

Scenario 2.
When work is completed and it is necessary to compare what was intended to happen with what actually happened.

Scenario 3.
When your intended sub-contract start dates were delayed and your contracted stage completion were delayed thereby.

Scenario 4.
Any other circumstance that you can think of.

How would you allocate:

TIA - IasP - AB v AP - ABbF or any other acronym to the above scenarios.

I look forward to your response.

Best regards

Mike Testro

Replies

Scarllet Pimpernel
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I agree that as built critical path may not be a suitable method to use.

I can be manipulated to suit the claimnant interest. The manipulation could be brazen to the point of being ridiculous, fantasy

I have this experience where the commercial manager and project manager wanted to save their ass. So the instruction is to manipulate the as built critical path to show the client impacted the delays.

It was so IQ 0 that as an experienced planner, I decided to leave the project team for good.

Thank you,
Scarlett
Andrew Flowerdew
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Mike,

It can be done but I don’t think I’ll be choosing to go down that route anytime soon if I can think of another suitable method to use.
Rafael Davila
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10-4
Sreejish Vishnu
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Hi Rafael thanks for that

Hi Andrew ,

I was not referring to my post on Critical As built method. i was referring to Mike’s thread all together.
Mike Testro
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Hi Andrew

I was talking to Paul Kelly of Gleeds recently and he outlined the Critical As Built method that seemed entirely plausible.

See my thread # 12

Best regards

Mike T.
Andrew Flowerdew
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Sreejish,

As-built critcal path programmes are usually so easy to discredit that people stay away from them - possibly the reason for the lack of response.
Rafael Davila
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Sreejish Vishnu

For your reference:

http://www.planningengineers.org/publications/papers_download.aspx?id=4

From above ABCP’S ARE OFTEN APPLIED IN CONJUNCTION WITH TIME IMPACT.

http://www.planningplanet.com/forum/forum_post.asp?fid=&Cat=7&Top=8238

Best regards,
Rafael
Sreejish Vishnu
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Thanks Mike.

I thought this topic would get a bit more warm response.
Mike Testro
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Hi Sreejish

I have never prepared a Critical As Built programme but I have had the method described to me by an Expert Delay Anaysis as follows.

1. Start from the end and work backwards.
2. Put down the start and end of the very last eactivity - say test and commissioning.
3. Then put down the start and end date of the previous activity - say floor zone static tests.
4. Draw a link between the point where the penultimate activity overlaps the start of the last activity.

(I know I know this is a SS Lead Lag Link but this is how it works.)

5. Continue backwards until you reach the very first activity and link that in to the start of the second.

You will now have a critical path set onto an as built programme with little doubt as to where the links should be.

All you have to do now is explain why the Critical as Built is different to the Critical as Planned to demonstrate cause and effect.

Best regards

Mike Testro.
Sreejish Vishnu
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CAB - its developing a logically linked dynamic programme based on the as built data. I just know it in theory. Could any of you who have done it in practice throw some light into it. My doubt is, when you make logical links out of the as built records, would it not be too arguable. I mean most of the links would not be hard and fast. So..you can put the links in that way or this way. To me, it sound too arguable. Off course when there was no As Planned programme at all in place, then CAB could be thought about.

IAP - is the most i have used. Because in the cases i dealt with a reasonably good as planned programme was available and only that was available. those were agreed between the C and CA almost by the time the original contract period was complete.

TIA & Windows - both will have to use the C’s monthly updates. Even in TIA when you have to impact the programme with an event, which programme will you use. It will have to be the C’s monthly update of the previous month. isnt it so. some of your earlier posts said the C’s monthly updates are not relevant for TIA. dont know if i mis-understood your statement.

To me the only difference between windows and TIA, when used retrospectively, is that windows consider all events together (within the window period) while TIA consider each event seperately. Though TIA would be more perfect, it may not be practically possible to consider each event seperately when there are too many events in place. i mean the cost of doing TIA analysis may offset the extra advantage which may be obtained out of doing it.

Andrew Flowerdew
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Ken,

Don’t disagree with what you’ve said and as you say, the CAB and IAP have less to go wrong, but they are also the easiest to pull apart and discredit. As the judge said in City Inn with regard to an as-built schedule:

"I am of the opinion… that an error in one logic link can vitiate the whole programme, and errors in a number of links will almost inevitably vitiate the programme.”

And common sense won the day in this one as far the method of analysis goes.

It’s not down to the experts to decide if the party has sufficient proof for its case, that’s the lawyers job, so as you say, experts will be asked to give an opinion on a case whatever the state of the evidence. In the case I referred to, the judge went out of his way to say the experts had done what was asked of them (para 240) - a dig at the instructing lawyers.

City Inn is also a case in my opinion that should have been thrown out for want of proof - now we’ve got a claim that has been thrown out for want of proof - potentially interesting times ahead. Other judges, arbitrators and adjudicators may follow suit. Food for thought for the lawyers but also for everyone else involved in a project - how good are your records?
Ken Sadler
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Hi Andrew,

Anything based on poor records will be suspect as you say. That’s the point I was looking to make - that the techniques discussed are not a "one size fits all" - each relies more on the information available than the scenarios that Mike described.

Poor information is two-fold - there’s the lack of as-built data and of course the poor planning / scheduling in the first place.

TIA / Windows need both AB data and a networked as-planned programme (APP) so there are 2 things to trip up on....

APvAB needs a realistic APP (which need not be networked) and AB records or an updated programme. Again, 2 things to go wrong, but perhaps more easily overcome.

CAB needs only AB records so only one opportunity to fail...

IAP needs only a Networked APP so again only one hurdle.

As I say, my view is that generally the information available is the key to deciding what can be done.

I agree that claims which lack proof ought to be "chucked out" but of course we prepare/defend such claims on a commercial (rather than purely legal) basis and we dont have the opportunity to dismiss them ourselves - we still have to produce a negative and sometimes positive case.

The common sense approach you refer to is akin to the point I made about GIGO (garbage in garbage out). If there is suspect information, isn’t it best to rely on one’s professional experience and opinion to produce a "persuasive" arguement (if the tribunal is intent on resolving the issue) rather than relying on the software which is instantly rendered useless when the legitimacy of its data is questioned. I certainly couldnt explain the algorithms that P3 uses to determine the results it produces, but I could have a stab at convincing a third party that party A caused most of the delay by common sense.

Andrew Flowerdew
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All,

One other thing the case says, although not a decided point:

Para 179: Haswell submits that Mr. Crane has not correctly applied the time impact analysis method in that, rather than applying the impact of the delaying event himself and assessing its consequences, he has used Costain’s monthly updated progress programmes for that purpose and, after the correction of certain anomalies, has accepted those programmes as correctly showing the impact of the delaying event. Mr. Purbrick, on the other hand, has carried out what he considers to be the more correct approach, namely to consider the state of the progress of the works prior to the inception of the delaying event and then impacting that event on to that programme in order to see what the software produces as the impact of that event. It is not clear to me what difference to the actual results these alternative approaches lead to but, if it becomes material to decide, I prefer the approach of Mr. Purbrick.

Para 180. The reason for that preference is that it eliminates any subjective distortion or manipulation (either advertent or inadvertent) in the production of the monthly progress programmes by Costain. Mr. Purbrick’s approach seems to me to be more rigorous and to be more in accordance with the accepted understanding of a time impact analysis approach, as agreed by the experts.

i.e - the preferred approach is NOT to use the contractor’s monthly updates in an analysis as they may have been manipulated. So next time you’re tempted to manipulate your programme to support your company’s case, if it all ends in a formal dispute, just remember that those programmes will be consigned to the bin and you’ll be in the position of having to argue that your own programmes were wrong!!!!!

Have made this point in previous threads but it’s the first time I know of that there’s been some judicial opinion on it.
Andrew Flowerdew
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Ken,

If few records exist, will any method give a better result.

A TIA based on poor records will give...
A collapsed as-built based on poor records will give...
A windows analysis based on poor records will give...
Common sense based on poor records will give...

Which one, if any, gives a result that can be relied on.

The case refered to dismissed the prolongation claim for want of proof - haven’t seen that in quite some time as more recently the courts have tended to make their own mind up when evidence has been lacking. This time the judge just chucked the claim out - and I support that approach. Actually in that case the experts had answered what had been asked of them but the judge decided it wasn’t sufficient. But it does raise the question of will any analysis in the future based on little evidence be sufficient proof. The level of proof is maybe back in the equation, something that the UK courts really haven’t vigorously enforced for quite a while.

(PS. Window’s and TIA will both usually pick up the monthly updates.)
Ken Sadler
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Hi all,

Time Impact Analysis (TIA) is often confused with Windows Analysis, since they both require the same basic information - that is a logic-linked as-planned programme (or updated version thereof) and as-built records.

The difference (though not picked up in the case text Andrew refers to) is in the periods of anaylsis. Where a windows analysis will set arbitrary time-periods in which to assess the events (usuallu monthly), the TIA will usually set the periods at the start and end of the delay events themselves.

Its a subtle difference but with TIA one assumes that the events are known, wheras in a windows analyis, the effects are established first and then the causes are legitimised if they fit.

As with all these things, it depends to a certain extent on the form of contract but more importantly on the information available. Of course a windows anaylsis or TIA is generally thought to be the "best" and indeed is the method recommended by the SCA Delay & Disruption Protocol. However, back in the real world, we rarely get a reliable and reasonable as-planned programme with logic links and decent AB information together. The other problem is that for all but the simplest projects, the TIA can get fiendishly difficult to understand without reliance on software. Whilst some still advocate this, it is preferable to provide your own expert opinion and avoid the "garbage in- garbage out" problem.

Just my humble opinion

Good post Mike.

Regards

Ken
Andrew Flowerdew
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Hi Mike,

Think I’ll play devils advocate here!

TIA can be used for all and if the records aren’t good enough, throw the case out for want of proof, not that the following very recent case says this:

http://www.bailii.org/ew/cases/EWHC/TCC/2009/B25.html

para 175 onwards - although this is a money case and not an eot case, it raises some interesting questions.
Sreejish Vishnu
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Hi Mike

thanks for the thread

Case - 1 - As planned impacted method or TIA could be used.

case - 2 - TIA or ’As planned but for’ if possible. But I personally feel APBF would be very difficult to come out with.

Case - 3 - an as planned vs as built could be used. depending on the situation may be other methods could also be used.

Above are my understanding, off course I am not an expert on this.
What the experts say?
Also, i feel, to start TIA its required to have a properly updated programme and good as built records. otherwise the job is going to be really tough. Similarly if the as planned programme is crap then Impacted as planned would not give a good result

So i think the method would also depend on the availability of programme, as built records etc.
Shah. HB
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Scenario 1 fits for TIA.
is it correct?
Paul Hodgson
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Mike

An interesting and worthwhile post, I agree that in my experience there is confusion as to what the specific terms imply.

Examining the scenarios you describe I would use the following techniques.

Scenario 1 demands a prospective technique I would use either Impacted As-Planned (IasP) i.e. impacting the delay event into the As-Planned or Baseline Programme, or Time Impact Analysis (TIA) i.e. impacting the delay event into the programme with the work done progressed to the time at which the event occurred.

Scenario 2 is retrospective analysis and As-Built v As-Planned (AB v AP) would be the preferred technique here.

Scenario 3 is complex, but I think I would be inclined to use IasP.

A 4th scenario worth considering is where there is no agreed Baseline, or where the works were not planned and no programme was prepared. Sadly scenarios which are still common place today. In such circumstances it is generally when the work is done (over time and budget) that a retrospective analysis is required. ABbF or Collapsed As-Built techniques could be used; also As-Built Critical Path (ABCP) is a useful forensic tool. Competent Planners are needed with these highly subjective techniques.

Not sure if I have picked the most appropriate techniques, but hopefully the results of your research and subsequent postings will resolve the issue.

Regards
Paul Hodgson