Project Anti-Crashing Method

Fast Tracking VS Crashing the Schedule

Fast Tracking the schedule means to Revise the logic and do thing concurrently or in parallel which means that your manpower peak will be higher but it will be the same number of man-hours except for additional supervision.

A good rule of thumb is that sequential activities can sometimes be fast-tracked by up to 33%. In other words, if you're fast-tracking, you can start the second of two sequential activities when the first activity is 66% complete. So when you are 66% complete with the first conduit activity you can start the wire pulling.

Crashing the schedule means to reduce your durations but you will have to increase your man-hours because you need more men to do it in a shorter amount of time. You would shorten the duration of the activities on the critical path by throwing additional resources to the critical path without necessarily getting the highest level of efficiency. You might have to do several iterations because you crash one critical path then something else becomes critical. You will have increased cost in with this option

The following link might be of interest.

http://www.spiderproject.com/images/img/pdf/Construction%20CPM%20Conference%202020/Schedule%20Optimization.pdf

Thanks Rafael. I am familiar with Spider Project and SDPM. In next posts I want to cover DRAG and FLEX metrics. As I understand, the FLEX is your idea? Is it corect? 

Zlotan,

At a high level, I agreed with what you said, but on practice project crashing is not only about adding extra resources and not always crashing may have negative cost impact:

- If a project pay for effort, total cost of work will be the same, regarding how many resoucres were involved. 

- When we ask critical resoucres work extra hours, it could be no extra cost added to the project. If they are permanent resoucres, company often just gives them extra days off to compensate the extra time.   

- Critical equipment with a higher productivity maybe more expensive or may be not. 

I am sure PMs can offer more examples of crashing with out inreasing project cost.

Alex,

An idea Vladimir fine tuned to the maximum in ways I could not imagine.

Best regards,

Rafael

Alex

With everything in the world there are expections and you can always to do things differently. You are listing exeptions to the rules as opposed to me stating what typically happens. 

Sure if its the owners fault that you need to crash the schedule or fast track it and he does not want to give you a EOT then it will be on his dime.