Site layout considerations

Haulage roads

The roads within the site have to be planned and designed by the contractor.
Lengthy roads may be required to take excavated material to a dumping ground, or from a borrowpit to the construction site. They exclude any traverse over public roads. The design of such roads is related to the type of excavating machinery the contractor proposes to use. Motorized scrapers and balloon tyred wheeled loaders can pass over hard to moderately soft ground and will  not seriously disrupt the surface. In most cases roads have to be designed for haulage trucks, which can impose heavy wheel loads when laden. Roads for them must be of adequate thickness, suitably topped (or constantly regraded) to prevent rutting and ponding, and well drained. Any attempt to save money by building an access road of inadequate thickness, without proper drainage ditches either side and a surface kept to a camber to shed rainwater, is a false economy. It will quickly break up and cause repeated delay to the job. Flat tracked machines can pass occasionally over metalled, waterbound, or sprayed and chipped roads without causing much damage. Machines with gripped tracks, such as large dozers, will quickly break up the surface of any road. The consequence of the foregoing is that internal roads on site have to be designed according to the anticipated usage of them. For maximum output from motorized scrapers it is important that haulage roads should have easy gradients. Laden haulage trucks are also frequently slow on steep gradients, both uphill and downhill. Mud is a particular nuisance when trucks have to go on public roads; frequent cleaning of the road and hosing of traffic leavingthe site will be needed if public objection is to be avoided.

Planning bulk excavation

The order in which an excavation is to be undertaken has to be planned. The excavating machine must be able to work to its maximum capacity attended by a continuous flow of dump trucks in and out. As bulk excavation proceeds, formation trimming and minor excavation will follow, then the placing of fill or concrete. For speed of execution these follow-on operations will need to be started before the bulk excavation is completed. Hence the excavation must be planned in such a manner that the different operations carried on simultaneously do not interfere with each other, and that excavating machines can withdraw without difficulty after their work is completed.

Concrete production plant

This needs to be positioned to give easy delivery to the parts of the work where the main concrete is required. Delivery lorries to the stockpiles of aggregates should preferably not follow the same routes as muck-shifting plant, or they will pick up mud and track it into the aggregate bays. The bays should have concrete floors laid to a fall so the aggregate can drain.
Power generators and compressors These may need to be housed, even if mobile, because their noise can create a nuisance to local residents. Their siting should be such that the noise they  create is blanked off from any residences. Even though the noise from a construction site may be music to the ears of a civil engineer who likes to hear the job humming along, the public at large take a diametrically opposite view.

Authorization of night working may be difficult to obtain if attention is not paid to reducing noise as much as possible.

Extra land

Extra land outside the site or extra access to the site can be obtained by the contractor if he so desires, provided it is not disallowed under the contract, and the contractor gets the necessary permissions, wayleaves, etc. and bears all costs involved.

Main offices

The contractors main offices and stores need to be near the site entrance. Most vehicles carrying materials to site must stop at the checkers office, and it is convenient to have this near the agents offices and the stores. The resident engineers office should not be far away from the agents offices, so that easy communication is maintained at all staff levels, and there is economy in providing telephone, heating, lighting and sewerage.

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