CE 366 PROJECT MANAGEMENT AND ECONOMICS Robert G. Batson, Ph.D., P.E. Professor of Construction Engineering The University of Alabama

Chapter 9: Project Time Management 2

Time Management System Upon implementing the project plan, progress meeting the schedule must be monitored Conditions will arise that disrupt the original plan and schedule Managers at various levels attempt to manage resources in a way to meet the current “official schedule” When schedules being to slip, the system of progress feedback should alert responsible managers up through the PM These regular reports are part of the repetitive “time management cycle” in Figure

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Aspects of Time Management The project network (or Gantt chart), with current start and finish dates for each activity, is the framework for schedule control –records the “official” start and finish dates –can be used to deduce impacts of activity schedule slippage Review of activity status reveals which activities have completed, which have started, and whether these are ahead or behind schedule -- and by how much Lagging items are analyzed for impacts (if left alone) and for alternative corrective actions, then action is taken The “baseline” schedule will become increasingly inaccurate as “actual” times occur, and must be updated periodically; importantly, everyone must be working off the current baseline 9.2

Key-Date or Milestone Schedules The higher the level of management, the less detailed the progress reports must be –Owner or his architect-designers –Construction company upper management –Project manager and other field managers –Craft supervisors A hierarchy of schedules is used Early start and finish times → Scheduled times Late start and finish times → Required times Actual start and finish are recorded and compared Figure 9-2 is based on the planned schedule in Figure 5.4, using dates from the project calendar Figure 5.5, and is intended to show progress to major milestones 9.3

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Detailed Schedules The highway bridge PM saw the opportunity to delay “Move in” by up to 12 days, and not affect schedule nor resources; he took 9 days and so first three weeks are scheduled as in Figure 9.3 Detailed schedules are needed by field supervisors and subcontractors –only next 2-4 weeks –shows free float (but not total float), each activity –does not show material delivery date or status Project scheduler monitors total float, a “reserves” for PM to allocate Revised tables and/or Gantt charts are issued regularly by the project scheduler (see Section 9.7 for frequency) Project expeditor monitors material status for PM, and must inform project scheduler of impending late deliveries 89.4

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Progress Reporting Frequency of reporting (daily, weekly, monthly) is determined by need for management control –level of management –size and pace of the project –which activities are critical and/or behind schedule Progress measurement requires direct visual observation by PM or engineer of P = percentage complete or W = work units in place; then use Working days to complete = D (1- [P/100]) or D (1- [W/Total]) Graphic display, in the form of Gantt charts, is used to visualize overall project status for activities completed or in-progress (see Figures 9.4, 9.6) –These are output of project scheduling software –Project network must be kept up-to-date and CPM used to analyze alternatives, and update schedules, upon which the bar charts or tables are based 9.5

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Progress Analysis At the weekly progress review: 1.What is the status of currently identified critical activities? –Finished by scheduled EF=LF, no problem –Started late, but not finished -- any way to catch up? –Finished late, then project scheduled completion will be delayed according to the number of days late 2.What is the status of current non-critical activities? a.Use a late-start activity sort -- Any activity that missed its LS date puts the project “behind” b.Use a late-finish activity sort – Any non-critical activity that did not finish by its LF date generates a new critical path for the rest of the project, and the project completion will be delayed according to this number of days [Can use total float to determine same information as in b.] 3.See example on p

Progress Analysis leads to Corrective Action Each progress report leads to progress analysis on –Activities –Material delivery dates and equipment on-site dates –Subcontracted work Corrective action is taken when –Activities fall behind their late start or late finish dates –Substantial delays of resource availability are indicated –Time duration of future activities are now indicated as underestimated –Any logic change to work yet to be performed Corrective action options are determined in progress meetings (may be more than one, for each problem) Corrective action(s) attempt to maintain the current critical path or minimize the extent of lengthening in a recalculated critical path; the efficacy of such action(s) can only be known accurately by incorporating them into CPM runs [Impacts on resources—check too] 9.7

Network Updating As deviations from plan occur, either planned actions or unanticipated events (top p. 216), the network and its output lose accuracy Network updating is needed –Trial updates to test proposed corrective actions –Permanent updates, perhaps on the same schedule as the progress review meetings or transmission of detailed work schedules –Project time control must be based on current job model -- the time conditions on all remaining activities Focus is on – Rescheduling the work yet to be done – Using current project status as a starting point – Incorporating approved changes as in Figure

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The Highway Bridge Update on July 21 The information is Figure 9.7 was incorporated Completed work item show only description and number Activities in progress have their duration = estimated time to complete A dashed line (data date) separates the network into two parts CPM forward pass and backward pass are completed, showing a change in critical path The project completion time of 71 days (with 6 days contingency still included) is acceptable Activity start and finish times are revised, as is the project schedule tables/Gantt charts 9.9

Scheduling Software The software package in use enables the project scheduler to: –Perform trial updates and determine their schedule impact (the estimator would likewise estimate incremental costs) –Establish a new baseline with all necessary time condition information to manage the remainder of the project Maintain a record of field progress information, leading to progress reports and evaluation of new proposed actions or unexpected events Conduct resource leveling, activity acceleration, and other necessary studies on the remainder of the project 9.10

Communicating Schedule Information PM and field supervisors –Field supervisors must have confidence in project scheduler –Field supervisors must receive information in a form they can use –PM must hold supervisors accountable to meet schedules or be honest about falling behind PM and owner or his own upper management –Cumulative progress curves, based on early start and late start schedules, form a progress envelope; average progress curve splits difference –Periodically calculate progress to date (various metrics are suggested) and plot in the corresponding envelope -- See Figures 9-9 and 11-5 –Supports progress reported on Gantt charts or accounting tables alone 9.11

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