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Lecture 1 Planning the worksite

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CE 3221 Construction Technology & Methods
Lecture 1
Construction project worksite Planning
Site Layout
Site Layout and Temporary works, verification of boundaries
Site information board, Emergency telephone numbers
Fencing, hoarding for the protection of the general public to act as sound and
dust screens and to aid security arrangements at the site,
Flooding possibilities and Drainage of the site.
Ground water table
Underground Service lines
Adjacent Buildings
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The Site Office and Access
The site office would provide space for administration and for staff welfare.
Facilities for first aid and fire fighting equipment, with trained personnel.
Temporary water, electricity and sewerage connections.
Proper access for the delivery of materials
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Site Services
The diversion of any existing services such as sewer lines, water, gas,
power, telephone and drainage lines.
Obtaining temporary power, water telephone etc. Disturbance to
neighbors etc must be minimized. Determination of manholes to connect
up temporary toilet effluent etc.
Site Yard
Locating yards for rebar bending ,
Yard for the fabrication of formwork
Site welding & fabrication
Site maintenance workshop for repairs, servicing
Setting up site batching plants etc
Location for a tower crane.
Access and maneuverability for any mobile crane
Scaffolding
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Site Storage
Bulk materials and storage of materials vulnerable on exposure to elements of
nature
Timber should be stored under cover and should be stacked such that there is
adequate air flow
Reinforcement should be stacked off the ground on a hard standing area
Combustible material should be identified and stored separately
Flammable material should be stored in steel drums and should be isolated
from combustible materials
Storage of oxy acetylene cylinders
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Equipment & Tools
Safety equipment : fire extinguishers, first aid box, safety helmets, safety eye
protection, ear muffs, coveralls, eyebath,
Clearing the site : hand axe, long handle chopping blade, wheel barrows,
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Setting out:
Total Station, Theodoloite/level instrument, steel tapes, wire nails, hammer,
pegs, nylon rope, knife, timber stakes and red and white marking tape. Plumb
bob and line, set square, spirit levels.
Excavation :
Pickaxes, Shovels, wheel barrows, mamoties, crowbars (jimmy) , buckets,
mortar pans, cane baskets, dewatering equipment, materials for planking
strutting, shoring,
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Concrete work : Timber stop boards, masons trowels, straight edge, cube or
cylinder moulds, slump cone, shovels, wheel barrows, mortar pans, vibrators,
chistles, hammer, Air compressor, jack hammers
Formwork : Timber, Plywood, wire nails, Styrofoam, inserts, handsaws, set
squares, drills, planers, cross cut saws, bench vices, “G” clamps,
Rebar and steelwork : Bar benders, bar cutters, welding plant, angle grinders,
files, oxy acetylene flame, hack saws, binding wire, cover blocks, chairs
Plumbing : blow torch, Sand paper, PVC adhesive, Teflon thread seal tape,
monkey wrench, hack saw pipe vices,
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The Site Organization Chart
The site organization chart shows the hierarchy of the site staff and shows the
relationships between the site staff.
The organization chart will be constructed by specialization of task and/or
function.
The organization chart can be used to allocate authorities and responsibilities
to the staff associated with the works.
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Board of Directors
Managing Director
General Manager
HSE & QA
Construction Mgr
QS & Estimation
Dept
Personnel
Finance & Admin
Finance & Accounts
Info. Sys. Officer
Procurement &
Stores
Proj. Mgr. 1
Eng. Support
Services
Proj. Mgr. 2
Conc. Batch Plant &
Precast Yard
Fabrication Yard
Plant Mtce
Proj. Mgr. 3
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Features of an organization chart
Chain of command (Unbroken line of command : where everyone
reports to someone)
Each person in the chain of command should have only one direct
supervisor to whom he is accountable. (Unity of command )
Span of control (a supervisor has an appropriate number of direct
subordinates)
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Policy Regulations & Procedures
From the organizations policies a set of procedures and regulations will be
developed for the administration of the project site.
This set of procedures and regulations will provide the necessary
information and the guidelines for the staff and workmen to do their daily
tasks.
Procedures and regulations will be available for staff welfare,
procurement, quality assurance, equipment maintenance, communication,
safety etc.
.
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Regulations, Procedures & Work Instructions
For instance the worksite procedures pertaining to safety may require that
each supervisor/foreman conducts a daily safety briefing with their workmen
prior to commencing work.
This safety briefing will discuss the possible hazards that will have to be
faced during the course of the work and the steps to be taken to safeguard
against these hazards.
The set of regulations will specify the disciplinary measures that will be
enforced in the event of non compliance. Prohibition of alcohol consumption
during working hours.
A procedure will comprise of a set of work instructions.
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Communication
Communication within members of the site organization and with all external
parties associated with the project is an important aspect in construction
management.
Communication is a two way process by which information is transmitted
by the disseminator and is received and understood by the recipient.
Communication can take place via different media such as vocal media,
paper telephone etc.
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Decision Making
Managing construction work will require a number of decisions to be
taken throughout the construction phase.
Decision making will be relevant to every level in the organizational
structure.
The type and the nature of decisions will be different at different levels of
the organizational structure.
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For example the decision making that will confront the project engineer will be
different to the decisions that will have to be taken by the plant and equipment
foreman.
Most often decisions require a choice to be made between two or more
alternatives.
Whilst a prudent decision will be beneficial to the project an unwise decision
will be detrimental to the overall project.
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Meetings
Meetings are the common method used in a worksite to collectively discuss
the construction work.
The consultant/client may initiate a weekly or a fortnightly meeting to
discuss the progress and other matters directly related to the construction
work.
In addition to the meetings that are organised by the client/consultant the
project engineer may arrange for more frequent meetings with his site staff
in order to co-ordinate and execute the work activities.
One of the main areas for discussion will be the sharing of resources such
that it will give the best benefit for the project.
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A typical agenda for a site meeting
The progress of work:
Material procurement and material quality assurance
Labour; If adequate skilled and unskilled workmen are available
Plant ; If adequate plant with proper certification and with competent
operators is available
Health, Safety and Environment issues
Quality issues
Site instructions, change orders and variations
Progress payment certificates
Nominated sub contractors
Financial cash flows
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Planning & Monitoring at the work site
Planning is the determining in advance of what is to be done to execute the
project within the required time and to the specified quality.
Planning is essential as tasks have become more complex and lengthy.
Planning of the construction work is a continuous ongoing process.
The plans will require constant adjustment to accommodate delays,
construction constraints and other contingency requirements.
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Control and reporting
Control measures are necessary to ensure that the project objectives are
realized throughout the construction phase.
The first step in establishing controls is to communicate the specific
targets and goals that have to be achieved.
Once every officer is aware of these targets, then they would be expected
to perform to these targets.
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Controlling would involve the periodic and systematic assessment of
performance against the set targets.
Any under achievement will be apparent early enough to take steps
towards its rectification.
The most common methods of enforcing controls are to set up a system
of report generation, and their evaluation
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Project Planning
Planning is essential for all projects no matter how small they are.
Planning is to study the project and analyze its resources requirements in
terms of:
1) Time 2) Materials
3) Money
4) Men
5) Machines
Planning is to arrange in a logical order and to sequence the operations in a
manner that gives the best results in terms of minimizing the consumption of
the above five resources.
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Project Scheduling
Project Scheduling deals with the breakdown of the project into identifiable
activities, (WBS) ascertaining the requirements of time and resources for the
completion of the activities and identifying the relationships between the
activities.
Project scheduling will enable the various resources such as finance, materials,
equipment and personnel to be optimally deployed within the planned time
framework.
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Scheduling will integrate the estimated duration’s of all the activities
and highlight the critical activities.
It will determine the logical and technological precedence in the
performance of the activities and emphasize the constraints that may be
imposed by the availability of resources
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Planning & scheduling can be divided into the following steps:
1) Collect information about the Job, ‘The Project’. This information is
available from the drawings, the specifications, the site, the Bill of Quantities,
productivity of men and machines, etc.
2) Breakdown the Job into small tasks. (These are called activities).
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3) Select the most appropriate method of doing each task (Activity) and
allocate the most likely time that the activity will require for completion.
4) Define the precedence relation between tasks.
For each task you ask the question which task must be completed before
this task can start?
The word ‘must’ is used for physical or dependence logic such as the roof
can not start unless the walls or columns under it are completed”.
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The Bar Chart/ Gantt Chart
A bar chart or Gantt chart is the most common scheduling tool used for the
planning of a project.
This is a graphical time scaled representation of the project.
The project is first broken down into discrete identifiable activities.
The relationships between the activities are then identified so that a
sequence of activities can be established.
The time duration’s for each of the activities are then estimated together
with the resources required to complete the activities.
Each activity is represented by a horizontal BAR. The length of the bar is
scaled proportional to its duration.
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Preparing a bar chart
Breakdown project into activities.
Estimate durations
Establish relationships between activities (dependencies)
Decide sequence and logic.
Determine any overlaps, lags, simultaneous starts.
Draw bars (activities) on the time scale in the appropriate order that they
will be carried and on the basis of their earliest starts.
Observe that some activities may have floats
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Time Spans of Plans
Monthly or weekly short term plans are usually prepared based on the overall
Gantt chart.
From these short term plans the tasks necessary to complete the activities are
delegated appropriately to each member of the site organization
For the proper execution of the work it is imperative that each person in the site
organization is made aware of his exact tasks.
To fulfill his tasks the requisite resources should be made available and he
should be delegated with the authority necessary to execute the work.
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Hierarchy of Plans
Work plans will have hierarchies. This means that every work group understands
its specific goals.
Achieving this will depend on how well the objectives and goals have been
defined and delegated.
For instance the project engineer will have to plan for the proper execution of the
entire project.
The plant and equipment foreman will concentrate mainly on the planning in
relation to plant requirements, maintenance and deployment as well as arranging
for competent operators.
The site safety officer will concentrate on safety planning for the entire project.
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Delegation of work activities
Once the work activities have been identified responsibilities in executing the
work is delegated based on the organization chart.
Delegation completeness : Every necessary task is assigned
Delegation sufficiency : Each person should be delegated sufficient authority
to meet his responsibility.
Non-delegateable responsibility : No one can relieve himself of responsibility
by delegating his authority downwards.
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Materials Scheduling
A listing of all the materials required for a project has to be ascertained and
scheduled during the planning stages of the project.
Suppliers should be prequalified and selected well ahead of the
commencement of the work.
The selection of the suppliers should be based on price, their ability to supply
to a schedule and the quality of their supplies.
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Once the suppliers have been selected they should be informed of the
material delivery schedule so that they too can plan out their strategies for
supply.
Prior to placing any orders samples of materials should be tested for
conformance to the specifications and approval obtained from the
consultants.
Procurement orders should be placed such that there is adequate time for
the materials to be supplied to the worksite for incorporation in the work.
Similarly materials should not be ordered very much ahead so that they
will just be taking up storage space and also lead to possibilities of spoilage
and wastage.
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Maintaining Records
Maintaining proper records is extremely important as construction work at
times lead to various disputes.
Most of these disputes could be eliminated by maintaining proper records.
It is good practice to request each site officer to maintain a diary in which the
daily activities are recorded.
This will enable a review of the daily activities to be made and if it so requires
a proper record initiated.
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Quality Assurance
Most contracts may require a quality plan to be made by the contractor prior to
the commencement of the construction work.
The purpose of the quality plan is to ensure that the work is carried out in
accordance to the work specifications.
The quality plan will incorporate procedures to ensure that the materials and
workmanship conforms to the requirements
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Method Statements
A method statement is a document that describes how to do a task safely
with the optimum utilization of resources.
A method statement is a set of instructions or a plan for the work.
It describes in a logical sequence exactly how a job is to be carried out in a
safe manner and without risks to health.
It includes all the risks identified in the risk assessment and the measures
needed to control those risks. This allows the job to be properly planned and
resourced.
Whilst procedures and site instructions are more generic method statements
are more specific.
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The contents of a method statement will vary with the work, however, it
may contain:
Details of the individual responsible for the activity.
A description of the activity.
A description of how the work will be managed.
The location of the activity, its boundaries, means of access and how it is
segregated from other activities.
Plant and equipment required.
The procedure for changing the proposed method of work if necessary.
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A step by step description of the activities to be undertaken.
Precautions necessary to protect workers, and other people that could be
affected, including personal protective equipment and ventilation requirements.
Training procedures if required .
The need for specially-trained operators for certain activities.
Emergency procedures, including the location of emergency equipment.
The handling and storage of materials and pollution prevention procedures.
Temporary works designs.
The method for safeguarding existing structures.
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Setting out is the process of developing the physical positions of the grid lines
and corners of a building and is done by transferring dimensions form the
layout plan to the ground.
The setting out clearly defines the center lines, excavation outlines and
enables construction to be carried out according to the plans
During the design process when drawings are prepared a plan providing the
setting out details is prepared.
During the setting out process a datum level is also established
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