Answered by:
MS Project 2016. Calculation of labor for construction project.
Question

Hello,
the question is following. I have a construction project, in which we know the work hours to complete the task. Also, we have some possible dates (duration) of start and finish of the task. Now I have put this tasks, work and dates into MS Project to get a Gantt chart (with fixed work). So,
1st task  24200 hours  /010318/110418  72 Workers
2nd task  32000 hours  /310318/260518  72 Workers
3rd task  37000 hours  /080518/020718  82 Workers
After. I applied resourses (Workers) with needed amount to achive the task at the needed work hours and, as follows, duration.
But, aslo, as you can see, it is just resourses for one task = 72 workes for 1st, 72 workes for 2nd, 82 workers for 3rd and so on.
The question is, how to find the labour force flow at the construction site? So, for example, after completing 1st task this 72 workers will go to the 2nd task  it will be 26.05. So, the duration of 2nd task by this will be increased(we dont want this). So, we need to add some force to the start of the 2nd task  08.05, which will work alone till 26.05 (till the end of 1st task), and so on...how much workers do we need to complete 2nd task with such a schedule?
Thanks.
Answers

nikbetting,
If you are expecting Project to automatically resource load your tasks other than in linear (flat) fashion or one of the work contours provided by the Work Contour assignment field, you are out of luck. The only way you can set up the schedule you want is to manually load the assignments via the Resource Usage or Task Usage views.
For reference Project uses the work equation to schedule tasks
Duration = Work/Units
Only one variable of the equation can be fixed. So if you have fixed work, your scenario, you cannot also the fix the duration or fix the units. What you can do is to start with a fixed work task. Enter the desired work content and assign a resource. Project will automatically calculate the duration. In the example below I have a task with 40h work and a resource assigned. Project balances the work equation to give 7.5 days duration (a week and a half assuming the Standard calendar and an default 8 hr workday).
However, I need the work to be done in one week so in order to have Project recalculate the number of units (resources) required to perform this fixed work task I edit the calculated duration to be 5 days. Project balances the work equation by showing 1.5 units are required to perform 60h work in 5 days and this is reflected in the Peak field as 1.5 units.
Of course, this only works for level loaded assignments. To obtain other loading, you must manually edit the assignments.
Hope this helps.
John
 Edited by John  Project Saturday, December 9, 2017 6:01 PM updated
 Marked as answer by Dale Howard [MVP]MVP, Moderator Thursday, December 14, 2017 3:45 PM
All replies


nikbetting,
If you are expecting Project to automatically resource load your tasks other than in linear (flat) fashion or one of the work contours provided by the Work Contour assignment field, you are out of luck. The only way you can set up the schedule you want is to manually load the assignments via the Resource Usage or Task Usage views.
For reference Project uses the work equation to schedule tasks
Duration = Work/Units
Only one variable of the equation can be fixed. So if you have fixed work, your scenario, you cannot also the fix the duration or fix the units. What you can do is to start with a fixed work task. Enter the desired work content and assign a resource. Project will automatically calculate the duration. In the example below I have a task with 40h work and a resource assigned. Project balances the work equation to give 7.5 days duration (a week and a half assuming the Standard calendar and an default 8 hr workday).
However, I need the work to be done in one week so in order to have Project recalculate the number of units (resources) required to perform this fixed work task I edit the calculated duration to be 5 days. Project balances the work equation by showing 1.5 units are required to perform 60h work in 5 days and this is reflected in the Peak field as 1.5 units.
Of course, this only works for level loaded assignments. To obtain other loading, you must manually edit the assignments.
Hope this helps.
John
 Edited by John  Project Saturday, December 9, 2017 6:01 PM updated
 Marked as answer by Dale Howard [MVP]MVP, Moderator Thursday, December 14, 2017 3:45 PM

