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Hi everyone ,
I have a question
How can I make P6 to calculate the original duration by itself
( To give it a quantity and Productivity rate )
Duration = Quantity * Productivity rate
any body can help me please
Thanks
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Yes, Raymund, you are right - many planners use their tools for presentation of manually developed plans.
But I wrote about the aim professional project planner shall try to achieve. This aim is creating project model that includes all known and required project data, project constraints, dependencies, risks and assumptions. The rest (scheduling, budgeting, risk simulation, etc.) shall be done with the tool help. If the tool does not have required capabilities project planner shall try to find some workaround, if nothing found he/she shall look for another tool.
Raymund,
I do not agree with your statement. Tools are created for improving the results that can be achieved manually.
Project Planner shall create the perfect model that includes all required, existing and real life activities, resources and constraints, the tool shall suggest the best possible schedule that takes into account all initial data and besides shall answer to any what if question.
Regards,
Vladimi
Thank you Raymund,
I would not insist on your answer.
With this initial information any software including P6 will produce wrong results.
Raymund,
we do not discuss estimating, we discuss scheduling. You wrote that it is 100% correct in P6 but described the process of manual estimating that does not use P6.
I asked very simple question: what is activity duration in the schedule created by P6 that starts on Monday. In this case assumptions of activity volumes that will be done by one or another crew do not make sense - the schedule shall supply us with this information and calculate activity duration and volumes that shall be done by each crew.
You did not answer to my question.
The main purpose of a scheduling tool is planning for the future not merely taking record and not caring about the predictions.
Any scheduling tool shall be able to predict start of activity and adjust activity duration according to resource availability and estimated resource production rates. Any scheduling tool shall be able to predict the impact of the revised dates and durations in the overall resource leveling and schedule predictions as soon as there is progress.
If P6 cannot predict correctly the duration of the activity then P6 is a very poor planning tool good only to manually draw some bars that are very unreliable unless much manual input is done in an attempt to get it right. In complicated schedules this manual input will yield poor results.
We are talking about a single activity, just imagine hundred activities competing for common resources at the same time.
Vladimir,
In Estimation, Values shall be given as follows:
To Determine the Duration:
1. Quantity shall be given
2. Productivity Shall be given
To Determine the Productivity:
1. Quantity shall be given
2. Duration Shall be given
To Determine the Quantity:
1. Duration shall be given
2. Productivity Shall be given
In case the estimator assumes more than 2 Crews then each crew shall be allotted a different Quantity to execute (2 Activities). 2 Crews working in a single area is difficult to determine which crew will execute a portion of quantity that much. In any crew there is no uniform Productivity within a Time Frame. Say example 10CM per hour, this could fluctuate to more than 12CM in 10minutes or less.
In the scenario of one of the comments, how can estimators assures a 500 CM of excavation to be executed by two crews and that a crew will complete 300 or 200 CM? This can be absolutely determined only if the works are already completed.
Regards,
Raymund,
I suppose that you tried this task and your solution in P6 before answering that P6 (your solution?) is 100% correct.
Could you please upload a screenshot of P6 result for an activity starting on Wednesday?
What is this activity duration in P6 schedule?
IT IS 100% CORRECT IN P6.
WRONG - THE DISTRIBUTION OF WORK, RESOURCE ASSIGNMENT DURATION AND ACTIVITY DURATION VARIES DEPENDING ON WHAT DAY AND HOUR THE ACTIVITY STARTS.
IF ACTIVITY STARTS ON MONDAY
IF ACTIVITY STARTS ON WEDNESDAY
Every time the activity is delayed, the distribution of work is shifted, when you have many such activities and work on different hour shifts, different days it can become quite complicated. For a single activity shot you can use manual distribution of work among shifts for anything else distributing work by hand is nuts.
Rafael,
Say you have the following scenario: Activity 1 volume of work is 500 cm rock excavation, Resource 1 production rate is 10 cm/hr and works Monday, Tuesday and Wednesday 10 hrs/day, Resource 2 production rate is 15 cm/hour and works on Wednesday, Thursday and Friday 10 hrs/day. If activity starts on Monday: Activity will take 3 days 3 hours, If activity starts on Wednesday : Activity will take 2 days 7 hours. How do P6 changes productivity and activity duration when crew is selected based upon availability?
In P6 setting will be:
Crew 1 :
Budgeted Units = 30hrs
Budgeted Units / Time = 1person x 10hrs/day
Resource Calendar Day-Time = Monday, Tuesday, Wednesday (10hr/day)
Crew 2 :
Budgeted Units = 30hrs
Budgeted Units / Time = 1person x 10hrs/day
Resource Calendar Day-Time = Wednesday, Thursday, Friday (10hr/day)
Material Resource 1:
Budgeted Units = 500 cm
Budgeted Units / Time = 100cm/day
Resource Calendar Day-Time = Monday, Tuesday, Wednesday (10hr/day)
Material Resource 2:
Budgeted Units = 500 cm
Budgeted Units / Time = 150cm/day
Resource Calendar Day-Time = Wednesday, Thursday, Friday (10hr/day)
Regards,
Zoltan,
the question was about Planning by Quantity, but I did not find Quantity (Activity Physical Volume) in your advice.
Did you mean that activity duration will become smaller if to add driving resource and will not depend on the quantity of not driving resource? What if different resources assigned to an activity have different productivity? An example: earthwork is done by two excavators with different capacities and the crew includes trucks (sufficient amount), machinists and workers.
Zoltan,
What you have shown is a rudimentary calculation that depends on manual input prior to scheduling calculations, it is static and does not respond to the availability of different crews with different production rates. What you have shown is just a manual calculation not a productivity model.
The day of commencement of CPM activities is continuously changing as things do not happen as planned. In order to follow your statement I will ask you to please disclose how you model the following scenario using P6.
Say you have the following scenario: Activity 1 volume of work is 500 cm rock excavation, Resource 1 production rate is 10 cm/hr and works Monday, Tuesday and Wednesday 10 hrs/day, Resource 2 production rate is 15 cm/hour and works on Wednesday, Thursday and Friday 10 hrs/day. If activity starts on Monday: Activity will take 3 days 3 hours, If activity starts on Wednesday : Activity will take 2 days 7 hours. How do P6 changes productivity and activity duration when crew is selected based upon availability?
It is a single activity schedule, it cannot be any easier, just prove P6 can handle such simple scenario with a productivity model.
http://youtu.be/1_qqDYbdq3w
In shutdown jobs most activities are worked by several teams on different shifts having different production rates, they are very dynamic. Guessing by hand the start of hundreds of activities whose duration will vary and affect the start of others can be monumental and most probably will yield poor results.
Best Regards,
Rafael
Make the duration type Fixed Units.
Make the activity type resource dependent
add resources and then add manhours (budgeted units) to the resource this will determine the durations
increasing the resources will decrease the activity duration.
Raymund,
Of course productivity as well as activity durations are estimated are estimated values subject to variation, they are not deterministic, only volume of work can be calculated with enough precision as to be considered a deterministic value when scope is well defined.
At home construction estimating is a mature process, each company has its own standards based on prior experience, not using this knowledge make no sense at all. At times a few activities are not in the company standard because the company have never before executed such activity in such cases we use references such as RS Means to close the estimate. We understand the possibility of variations and consider some buffer in our estimates, from our records we know how activities and resources are subject to variations in production rate. Probabilistic methods such as Monte Carlo help us to determine the appropriate level of buffer for time and cost in a rational way.
You said: How do P6 changes productivity and activity duration when crew is selected based upon availability? Availability of Resources are determined on the same day the Activity will commence. Therefore, during Planning Process all values are estimates.
But the day of commencement of CPM activities is continuously changing as things do not happen as planned. In order to follow your statement I will ask you again to please disclose how you model the following scenario using P6.
Say you have the following scenario: Activity 1 volume of work is 500 cm rock excavation, Resource 1 production rate is 10 cm/hr and works Monday, Tuesday and Wednesday 10 hrs/day, Resource 2 production rate is 15 cm/hour and works on Wednesday, Thursday and Friday 10 hrs/day. If activity starts on Monday: Activity will take 3 days 3 hours, If activity starts on Wednesday : Activity will take 2 days 7 hours. How do P6 changes productivity and activity duration when crew is selected based upon availability?
It is a single activity model, it cannot be any easier, just prove P6 can handle such simple scenario.
http://youtu.be/1_qqDYbdq3w
You will get a better Monte Carlo model if considering the variation in production rate, definitively production rate is not deterministic. Make sure your software is capable of modeling the variations in production rate when running Monte Carlo.
In shutdown jobs most activities are worked by several teams on different shifts having different production rates, they are very dynamic. Guessing by hand the start of hundreds of activities whose duration will vary and affect the start of others can be monumental and most probably will yield poor results.
Best Regards,
Rafael
Raymund,
in construction industry there are production norms that define what time is required for executing one unit of volume for certain work type by certain resource type. Another option that is also used to define resource productivity as volume of work per time unit (usually hour) for certain activity and resource types.
Estimates are based on these norms.
I assume that construction industry uses different approaches in different countries. So please write about construction industry in your country (or list the countries about which you know).
Rafael,
In Construction Industry, there is nothing a standard of Productivity.
Calculation of Duration of an Activity are estimates and there is nothing calculated as fixed value.
If in your case the Productivity is unstable then the planner may use the average in order to get the estimated value of duration.
In P6, you have to input the Productivity rate and the Quantity so that Estimated Duration will be derived or vice versa if the needed Quantity to be produced per time is estimated.
P6 can also changes Productivity by using a different Resource Calendar.
How do P6 changes productivity and activity duration when crew is selected based upon availability?
Availability of Resources are determined on the same day the Activity will commence. Therefore, during Planning Process all values are estimates.
Raymund,
What you have shown is a rudimentary calculation that depends on manual input prior to scheduling calculations, it is static and does not respond to the availability of different crews with different production rates. What you have shown is just a manual calculation not a productivity model.
Best Regards,
Rafael
Set Duration TYpe as "Fixed Unit/Time".
In the Activity details Resource Tab... Right click to display Columns field of Budgeted Units and Budgeted Units/Time.
In the Budgeted Units input your Quantities while in the Budgeted Units/Time input the Productivity Rate. You will see the duration changes while changing the value of Budgeted Units/Time.
Hope this will help.
Raymund
Thanks for your reply
Then what should I do ?
how can I enter the quantity and Productivity rate to it ?
thanks for your reply
I sure that I can do it by P6
but actually I don't know how till now
Yazan, P6 has no fields for quantity and productivity.
If you need this look at Spier Project.
Hi,
Set Duration TYpe as "Fixed Unit/Time".
Email: PPadmin@planningplanet.com
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