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    Precidance Network1

    Uploaded by

    Rajesh Thorat
    The document discusses precedence network (PN) analysis, which is an alternative to critical path method (CPM) network analysis. A PN incorporates start-finish and finish-start logic as well as lags to depict relationships between activities. PN is well-suited for planning complex construction projects due to its ability to model job dependencies and constraints. The document provides an example PN for raft foundation construction and explains how to perform forward and backward passes to determine early and late start/finish times. Software is recommended to avoid tedious PN calculations. PN analysis can also be applied to repetitive construction works by prioritizing raft sequences and planning activities into work teams.

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    © All Rights Reserved
    Download as PPTX, PDF, TXT or read online from Scribd

    Precidance Network1

    Uploaded by

    Rajesh Thorat
    44 views26 pages
    The document discusses precedence network (PN) analysis, which is an alternative to critical path method (CPM) network analysis. A PN incorporates start-finish and finish-start logic as well as lags to depict relationships between activities. PN is well-suited for planning complex construction projects due to its ability to model job dependencies and constraints. The document provides an example PN for raft foundation construction and explains how to perform forward and backward passes to determine early and late start/finish times. Software is recommended to avoid tedious PN calculations. PN analysis can also be applied to repetitive construction works by prioritizing raft sequences and planning activities into work teams.

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    PRECIDANCE NETWORK1

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    The document discusses precedence network (PN) analysis, which is an alternative to critical path method (CPM) network analysis. A PN incorporates start-finish and finish-start logic as well as lags to depict relationships between activities. PN is well-suited for planning complex construction projects due to its ability to model job dependencies and constraints. The document provides an example PN for raft foundation construction and explains how to perform forward and backward passes to determine early and late start/finish times. Software is recommended to avoid tedious PN calculations. PN analysis can also be applied to repetitive construction works by prioritizing raft sequences and planning activities into work teams.

    Copyright:

    © All Rights Reserved
    Download as PPTX, PDF, TXT or read online from Scribd
    Download as pptx, pdf, or txt
    44 views26 pages

    Precidance Network1

    Uploaded by

    Rajesh Thorat
    The document discusses precedence network (PN) analysis, which is an alternative to critical path method (CPM) network analysis. A PN incorporates start-finish and finish-start logic as well as lags to depict relationships between activities. PN is well-suited for planning complex construction projects due to its ability to model job dependencies and constraints. The document provides an example PN for raft foundation construction and explains how to perform forward and backward passes to determine early and late start/finish times. Software is recommended to avoid tedious PN calculations. PN analysis can also be applied to repetitive construction works by prioritizing raft sequences and planning activities into work teams.

    Copyright:

    © All Rights Reserved
    Download as PPTX, PDF, TXT or read online from Scribd
    Download as pptx, pdf, or txt
    of 26

    PRECEDENCE

    NETWORK (PN)
    Introduction
     Precedence Network Analysis (PNA)
     Precedence Diagramming Method (PDM) or
     Activity-on-node Network.
     In CPM/PERT networks, activities are connected
    according to the finish-to-start logic,

     A PN incorporates the concept of delays (lags) while


    depicting the relationship of various start and finish
    activities.

     The PN is best suited for planning complex


    construction projects.
    Precedent
    Logic

    Job logic Constraints


    logic
    Job dependency logic arises from the
    shows the sequence in restrain on start and
    which the jobs or completion of
    activities progress activities imposed due
    to construction
    process at site.
    FS FF

    SS SF
    Multiple PDM relationships
    Example.
     PN of raft foundation Code Description Dur
    The various activities
    involved in the raft A Excavation 4
    construction are as B Blinding base 2
    follows:
    C Steel fabrication 5
    Transportation of
    D 1
    rebar steel to site
    Formwork setting
    E and rebar fixing 3
    Raft
    F concreting 2
    Forward Pass
     EST of starting activity = 0

     Activity A, Node – 1
     EST1 = 0

     EFT1 = EST1 + d1 = 0 + 4 = 4

     Activity B, Node – 2
     EST2 = EFT1 + delay = 4 + 2 = 6

     EFT2 = EST2 + d2 = 6 + 2 = 8
     Activity C, Node – 3
     EST3 = 0

     EFT3 = EST3 + d3 = 0 + 5 = 5

     Activity D, Node – 4
     EST4 = 5

     EFT4 = (EST4 + d4 ) or (EST2 + 1FS) Greater one

    = (5 + 1) or (6 + 1) = 7 Compute
    till end
    Backward Pass

    Node No. Activity Duration LFT LST

    6 F 2 12 10

    5 E 3 11 8

    4 D 1 8 7

    3 C 5 7 2

    2 B 2 8 6

    1 A 4 4 0
    Draw a Precedence network and
    analyze…
    Is this a precedence network?
    Why softwares are required?
    ………..to avoid tedious calculations
    Repetitive Works Network
     The PNA technique can be usefully applied to
    prepare the network plan of projects involving
    repetitive works..
     Network for construction of subsequent rafts can be
    easily developed as follows:

     Decide the order of priorities of construction of rafts.


     Plan each construction activity into a work-team with the
    assigned manpower, equipment and other resources
    required for its completion.
    What we have learnt uptill now in Scheduling?

    1. Network analysis
     CPM
     AOA
     AON ( Precedence)
     PERT

    2. Resource leveling/ smoothening …..Resource constraint scheduling

    3. Crashing CPM schedule for Cost / ….Cost/ time optimized scheduling


    time optimization

    4. Updating CPM network

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