Important Concepts in Construction Management

Important Concepts in Construction Management

• Military organisation is known as – Line organisation

• The artificial activity which indicates that an activity following it cannot be started unless the preceding activity is complete is known as – Dummy

• Programme Evaluation and Review Technique is Event oriented.

• For the execution of a project a contractor is Person, Firm or Agency.

• The difference between the maximum time available for the job and actual time it consumes is called Total float

• The difference between the latest start time and earliest start time of an activity is called Total float.

• The difference between the earliest finish time of an activity and the earliest start time of its successor activity is called Free float of the activity.

• Henry Gantt developed Bar charts for planning & scheduling of projects in 1900.

• Mile Stone charts were invented in the year of – 1950

• The time by which activity completion time can be delayed without affecting the start of succeeding activities, is known as Free float

• The performance of a specific task in CPM is known as – Activity

• The activity is the time consuming part of a project.

• The beginning and end of a job are called Events.

• Logically and Sequentially connected activities and events form a network

• An activity is a – 1.Excavation for foundation, 2.Curing of concrete, 3.Setting of question paper .4.Preparation of breakfast

• PERT analysis is based on – Optimistic time, Pessimistic time, Most likely time

• Site order book is used for recording – Instructions by the executive engineers

• An activity of a project is denoted by an arrow on the net work.

• The tail of the arrow indicates the start of the activity.

• The head of the arrow indicates the end of the activity.

• Each activity consumes a given time.

• The most popular type of organisation used for Civil Engineering Constructions is – Line organisation

• Time and progress chart of a construction is also known as Bar chart, Gantt chart, Modified Mile stone chart and Critical path method chart.

• The time which results in the least possible construction cost of an activity is known – Slow time

• While filling the tender for any work the contractor considers – 1.Site survey, 2.Availability of construction materials, 3.AvailabiIity of labour, 4.Study of specifications.

• Works costing less than RS 20,000 are treated as – Minor projects

• Bar charts are suitable for – Minor works

• The salient features of functional organisation are -• 1.Strict adherence to specifications, 2. Separation of planning and design part, 3.Each individual maintains functional efficiency, 4.Work is properly planned and distributed.

• Final technical authority of a project lies with – Chief Engineer

• Construction team includes – Engineer, Architect, Owner and Contractor

• The difference between the time available to do a job and the time required to do the job is known as – Float

• PERT is – 1. An analytic in concept, 2.Limited of event oriented diagrams, 3.Used for research and development projects, 4.Based on three time estimates for activities linking up two events.

• Critical path method – 1. Is an improvement upon bar chart method, 2.Provides a realistic approach problems, 3.Avoids delays which are very common in bar charts.

• Frederick W. Taylor introduced a system of working known as – Functional organisation

• The PERT event from the – 1.Digging of foundation started, 2.Digging of foundation completed, 3.Layineg of concrete started, 4.Laying of concrete completed

• The first method invented for planning projects was – Bar chart method

• Railway projects are treated as – Heavy construction

• CPM is – 1. Synthesising in concepts, 2.Built of activities oriented programme, 3.Based on time estimate, 4.Used for repetitive works

• Critical path lies along the activities having total float – Zero

• Optimistic, Pessimistic, Most and Expected time estimate refers to activities.

• The difference between the earliest start time and latest finish time of any activity is the maximum time available for the activity.

• The main principle of an organisation is – 1.Unity of command, 2.Effective control at all levels, 3.Delegation of authority

• Residential buildings are treated as – Light construction

• A CPM family includes CPA (Critical Path Analysis),. CPP (Critical Path Plotted), MCE (Minimum Cost Expenditure), CPS (Critical Path Scheduling).

• The critical activity has – Zero float

• Pre-tender stage requires – 1.Acquisition of land, 2.Selection of site, 3.Formation of alignment of work, 4.Formation of designs and preparation of estimate

• The estimated time required to perform an activity is known as – Duration

• The final selection of a construction site is done by – 1.Departmental representative or user, 2.Local civil authority representative, 3.Representative of engineer authority, 4.Representative of administration

• Modular co-ordination of construction means proper – Planning, Designing, Execution

• CPM analysis is activity oriented, PERT analysis is event oriented.

• CPM does not make any allowance for the uncertainties in the duration of time. In CPM the time is related to cost.

• The duration between the earliest start time of the preceding event and latest finish time of the succeeding event is called ‘Float’.

• The duration of time by which an activity can be delayed without affecting the succeeding activity is called Free float.

• The float which affects neither the processor nor the successor activities is called Independent float.

• The difference between total float and free float is called Interfering float.

• The first stage of a construction is – Preparation of estimate, Survey of the site, Initiation of proposal

• For completion of a project, the critical path of the network represents – Minimum time

• In CPM analysis – 1.Emphasis is given to activities, 2.Uncertainties are not allowed, 3.Activities are represented by arrows, 4.Beginning and end of an activity is denoted by nodes.

• The technique for establishing and maintaining priorities among the various jobs of a project is known – Critical ratio scheduling

• For the supply of materials for concrete, form work reinforcing and placing of concrete, removal of form work and curing of concrete, number of bars required on bar chart is 1.

• Concrete cured represents an event.

• The various functions under each activity are shown by one bar on Bar Charts – Only approximate percentage of the completed work is reported

• Frequency distribution curves 1.Having a single lump are called uninodal curves, 2. If symmetrical are called normal curves, 3. If not symmetrical are called skew curves.

• The main disadvantages of line organisation are – 1.Rigid structure, 2.Extraordinary delay in communications, 3.Top level executions over work

• The difference of latest occurrence time and earliest expected time is called Slack.

• The activities connecting the events having zero slack lie on the critical path.

• The critical path consumes the maximum time.

• Earliest occurrence time of the event from which the activity arrow originates is called Earliest start time of the activity.

• Earliest occurrence time of the event from which the activity arrow originates plus the duration of the activity is called Earliest finish time of the activity.

• The latest occurrence time of the node of which the activity arrow terminates minus the duration of the activity is called Latest start time.

• The latest occurrence time for the node at which the activity arrow terminates is called Latest finish time.

• Power stations are generally treated as – Industrial construction

• Earliest expected time is denoted by TE, Latest occurrence time is denoted by TL, Contractual obligation time is denoted by TS.

• Latest occurrence time is taken as contractual obligation time.

• Forward pass is used for calculating Earliest expected time.

• Backward pass is used for calculating the Latest occurrence time.

• Completion of an activity on CPM network diagram is generally known as Event, Node and Connector.

• A dummy activity is – 1.Artificially introduced, 2.Represented by a dotted line, 3.Does not consume time.

• The float may be positive, zero or negative.

• If the float is positive and the activity is delayed by a period equal to its total float, the completion of project is not delayed.

• If the float of an activity is negative, delay in its performance is bound to delay the completion of project.

• If the float of an activity is zero, the activity is critical and any delay in its performance will delay the whole project.

• An event is indicated on the network by a number enclosed in circle, square, triangle and ellipse.