information to a barchart. Scheduled dates are much easier to read on a barchart. Figure 2-16 is a level III barchart sorted by early start date. All of the construction activities are listed down the left-hand side. A time scale is at the top of the page. The time scale goes from the first workday of the project to the last workday. The start date, finish date, and duration of each construction activity is shown on the barchart. The double horizontal dash lines represent critical construction activity durations. The single dash lines represent noncritical activity durations. Free floats are shown as dots behind each noncritical activity. For activities with no free float you have to look at the activity that they are sharing floats with to find the total float. For example, the total float for activity 4000 is shown behind activity 4005. No free float on 4000 means you cannot delay it without delaying 4005 also.
Resource leveling involves matching the construc- tion activities scheduled to the crew size available. You want the entire crew to be gainfully employed every day. You also want to keep up with the scheduled work
Figure 2-15. - Logic relationships.
and not fall behind. To perform resource leveling, you need a known crew size, a time-scaled schedule, and a histogram. The histogram shows how many people in each rating are required on a daily basis to complete the tasks scheduled. You can create these documents by hand or computer. Figure 2-16 represents only the first page of a level III barchart. Look at figure 2-16 and you see can the resource histogram at the bottom of the page. The numbers give the required resources needed to complete the
critical activities scheduled for each day. These activities cannot be moved without delaying the project!
The primary task in resource leveling is to schedule the
noncritical work as you have people to do the work. In figure 2-17 the total float for noncritical activities has been penciled-in in the space between the activity numbers and descriptions. The crew sizes for each noncritical activity also have been penciled-in next to the activity start date. The total crew size in this example is 7. You have resource leveled this project for a small detachment scenario. Here the prime/sub arrangement is not practical and extensive cross-rate use of personnel is common.
In figure 2-18 notice the resource leveling process was started by committing to doing the critical path as shown and plugging in the resources. These resources can be figured by the computer or drawn in manually at the bottom of the page. The critical path will obviously not keep the entire crew busy (see the original total resource numbers at the bottom of the page). The noncritical activities are shown on their early start dates, but you may need to delay the start dates if you lack the people to start the noncritical activities at that time. If you delay the start of a noncritical activity, you want to schedule its start as soon as you have people (available those days where total resources are less than 7).
Figure 2-18 has been resource leveled. The activities were scheduled beginning with the least amount of total float to those with the most total float. Activity 2050 was scheduled first, then 2090, 3020, 3010, 4000, 4005, 4030, and 4010. This process should be continued through the rest of the project. Notice that there were not yet any personnel to schedule for activities 2010, 2020, 2030, 7010, or 7020. These resources would be carried over to the next page of the barchart. We also did not schedule activities 6020, 8080, 9010, or 8095. Even though they have the least amounts of total float, these activities have early starts late in the project and can be rescheduled later. Remember the activities are shown by early start dates and can be moved forward only,
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