Site Layout In Construction

by CIVIL-GUY on MAY 16, 2010 in CONSTRUCTION WORKFORCE

T

he construction of a building can be considered as production with temporary factory. The building site is the ‘factory’ where the building contractor will make the product on-site. Site layout can be defined as site space allocation for material storage, working areas, accommodation units, plant positions, general circulation areas, access and egress for deliveries and emergency services.

The construction site layout would focus on a construction project of a building and the elements on that it should have. The building site has to be carefully controlled so that:

• The operatives of construction have the right machinery in the most advantageous position.
• The materials are stored with care to be readily available and not interfere with general site circulation.
• An adequate storage spacing for construction materials on site.
• Site accommodation and complete facilities for the construction workforce..

Knowledge of The Site

It is crucial to acquire knowledge of the project site before setting out the site layout. The knowledge about the project site can be obtained from:

• Contract Document
• Site Investigation
• Information from Local Authority

Knowledge from Contract Document

Plant Schedule

– This can be prepared in the form of a bar chart and method of statements showing the requirements and utilization, which will help in deciding the right equipment and the space for plant accommodation that will be needed on site.

Material Schedule

– The primary data can be obtained from the bill of quantities. The contractor can predict the delivery periods and the amount or size of the site space and/or accommodation required.

Labour Summary

– Basic data from the bill of quantities and pre-tender bar chart programmed to establish the number of sub-contract trades required. Also, the quantity and type of site personnel accommodation are required.

A Set of Hand Augers for Soil Sampling

Knowledge from Site Investigation

Access to Site

– All information regarding on-site and off-site access, road and rail facilities, distances involved and bridge weight or height limitations on approach routes.

The Workforce

− About the travel distances, availability of local trade contractors, specialist contractors, local rates of pay and facilities to be provided, site accommodation, catering, health and safety equipment, etc.

Temporary Services

The Common Services Trench

– Available and adequate power and water supplies together with rates of payment or services already on site, diversion required and the time element involved in carrying out any necessary diversion together with cost implications.

Security Matters

– Local vandalism and pilfering record (history if needed), security contractors facilities, need for night security, fencing hoarding requirements to prevent trespassing and to protect the people in the vicinity.

Site Clearance and Demolition

– The neighbouring properties, preservation orders, trees, demolition problems and special insurance considerations.

Ground Composition

– All the general site conditions, such as the nature of the soil, soil classification, the height of water table, flooding risks, tidal waters, site elevation, and so forth.

Knowledge from Local Authority

From the planning, highways, and building departments

– Permission to develop the project site.

To ascertain the viability of the proposal

– Access roads and facilities are adequate.

Proposed alteration and improvement are acceptable

– Follow the given outline for approval.

The detailed planning of construction application is necessary for authority approval…

Planning Site Layouts

When planning construction site layouts, the following must be taken into account:

• Site Activities
• The Efficiency
• Facilities and Accommodation

Site Activities

The time needed for carrying out the principal activities can be estimated as follows:

1. the data obtained previously for preparing the material such as concrete, where the rate of placing concrete will be determined by the output of the mixer,
2. labour requirements, for example speed of transporting the mix to the appropriate positions.

Alternatives which can be considered are:

– Provide more than one mixer, regulated supply of ready mix concrete or on large contracts, pumping the concrete to the placing position.

All alternative methods for any activity will give different requirements for staff numbers, material storage, access facilities and possibly plant types and numbers.

Efficient Handling and Storage of Materials

The Efficiency

To achieve maximum efficiency, the site layout must maintain the desired output of the planned activities. This will depend mainly upon the following factors:

• Avoidance, as far as practicable, of double-handling materials.

• Walking distances are kept to a minimum to reduce the non-productive time spent covering the distance between working, rest and storage areas.

• Avoidance of loss by the elements;

– provide adequate protection for unfixed material on site, thereby preventing time loss and cost of replacing damaged materials,

– Proper store-keeping arrangements to ensure that the materials are of the correct type, in the correct quantity and are available when required.

• Avoidance of loss by theft and vandalism;

– provide security arrangements by having adequate hoardings and fences.

• Avoidance of loss due to pilfering by site staff;

– provide an adequate system of stores’ requisition and material checking procedures.

• Minimizing on-site traffic congestion;

– plan delivery arrivals,

– provide adequate parking facilities for staff cars and mobile machinery when not in use,

– provide sufficient turning circle room for the type of delivery vehicles likely to enter the site.

Facilities and Accommodation

Within the site layout, the main contractor is obliged to provide a safe, healthy place of work and a safe system of work, plant and equipment which are not a risk to health as well as the environment:

• A safe and healthy place of work,
• Secure access and egress from the place of work,
• A safe and efficient system of work,
• Safe items of plant and equipment,
• Suitable and adequate training, supervision and instruction in the use of equipment,
• Reasonable and appropriate Personal Protective Equipment (PPE),
• Material and substances which are safe to use.

Apart from legislative necessities, the central area of concern will be sizing, equipping and assigning a location to the various units of accommodations such as:

• Mess Hut or quarters
• Toilets and washing area
• First aid and medical rooms
• Offices – Contractor’s supervisory staff, Clerk of works, Reception of material or security
• Lock up store for materials and tools
• Storage compound for major materials such as aggregate, sand, cement
• Timber store and formwork fabrication area
• Reinforcement store and fabrication area
• Scaffold and misc. store
• Sufficient vehicle parking areas
• Plant and machinery areas such as tower crane, concrete deliveries, sand and cement storage, and site mixer
• Fencing or hoarding to mark a boundary
• Great services and welfare
• Site Identification for workers and visitors

Site Layout for Building Construction

The site layout can be divided into several sections, such as the main gate, hoarding fencing, uncovered storage area, covered storage area, car park, site office, access road/traffic in site, tower crane, workers mess, signboard, guard house, a workshop for machinery, and material or soil stockpile.

The Conclusion

Planning a site layout in practice will depend upon factors such as time and money. The need for careful site layout and site organization planning becomes more relevant as the size and complexity of the construction operation increases, especially where spare site space is minimal.