Project Scheduling 2 

Prepared by Sebghatullah Karimi(Junior Lecturer of Kabul Polytechnic University)

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Kardan UniversityCivil Engineering Faculty

Explain how the work environment, the construction contract, and the project scope influence the scheduling process. Explain the three types of project activities used in scheduling.Define milestone.Describe the characteristics of a network diagram.

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Work breakdown structure – The organization of the project into specific parts that can be coordinated and controlled. Activity – A well-defined, measurable part of the overall project. An activity must be suitable for assignment to a particular project team member, and it consumes both time and resources.Trade – A construction specialty, such as plumber, carpenter, welder.Submittal – A sample of an item to be procured for a project by a supplier or subcontractor. A submittal must be approved by the owner or designer prior to procurement.

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• A network schedule is graphical drawing of a logical sequence of events to complete a project. A network-based schedule is a powerful tool for the planning, development, and construction of sophisticated projects.

• The development of a network-based schedule follows a logical process that should involve most of the key project team members. Every network schedule must begin with a complete understanding of the project objective, as defined by the owner. The project participants then take this objective and break it down into tasks that provide the level of detail necessary to organize, manage, and control the project. Once these tasks are defined, the project team establishes the order in which the tasks are to be performed, such that the project will be completed in an efficient manner.

• To create the network, team members decide which activities must precede, succeed, or run concurrently with other activities. The end result of this process is a logic diagram that accurately depicts the order that the work will follow. 4

The preparation of a network schedule requires a careful analysis of three factors:The work environment. The work environment includes such consideration as the weather, site conditions, availability of building materials, access for deliveries, availability of power, and the amount of construction currently occurring in the region.The contract. A construction contract will typically include the project completion date, milestones, incentive clauses (which provide bonuses for early completion), liquidated damages clauses (which provide penalties for late completion), work rules governing safety and hiring requirements, and identification of materials and work that will be provided by the owner. All of these considerations will affect project organization and scheduling. The project scope. The scope of the project, as described in the drawings and specifications, is a major consideration in scheduling. Drawings and specifications are the source of all the materials and quantities used in the project and may also describe required construction methods.

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1. The first step in the networking process is to define the work breakdown structure for the project.

2. From the work breakdown structure, the team defines the specific activities that will make up the network diagram. An activity must be suitable for assignment to a particular project team member, and it should consume both time and resources.

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Construction activities can generally be characterized as one of three types: Production activities are the activities that define the actual physical construction of the project. Examples include Erect Concrete Wall. A well-developed schedule allows the project team to separate all activities of each trade in such a way that each contractor has a clearly defined scope of work without overlap or omission. Procurement activities involve the purchase of materials, equipment, and services for the project. Most procurement activities follow a logical sequence, beginning with the preparation of a submittal, the approval of the submittal by the owner or designer, the ordering and fabrication of the item, and then the delivery of the item to the job site..Administrative activities include required inspections by local officials or regulatory agencies, as well as permitting. Identifying these activities requires the involvement of all project team members, since normally no one person knows all the administrative requirements for a complex project. 7

A key event in a project schedule can be identified by the use of a milestone. Examples of milestones include the planned shutdown of electricity or water supply in order to make connections to existing utilities, the delivery of a certain phase of a project to the owner, or a city agreement that a road be opened by a specific date. Unlike an activity, a milestone cannot be assigned to a company or person and does not consume time or resources. A milestone is used simply to signify an important point in the life of a project.

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A network diagram is a pictorial representation of all activities that make up a project and the order in which these activities must occur to complete the project in an efficient manner. In order to develop the network diagram, the scheduler must answer the following questions for each activity:

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What activities must occur before this activity can be done?What activities must follow this activity?What activities can be accomplished at the same time that this activity is occurring?

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A typical example of a network diagram is shown at the top of Figure 9.4 in the Gould textbook. As you can see:The diagram is read from left to right.Activities are identified by rectangles (nodes) and connected by arrows.Each rectangle indicates a single activity.The network is continuous. Each activity, except the first and last, has both preceding and succeeding activities. Activities without predecessors are assumed to begin at the start of the project.Activities without successors are assumed to be complete when the project finishes.No activity can start until all preceding activities have been completed.

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