Some property owners may insist that a particular method of excavation should be used during civil works on their properties. Such people may not know the different factors that are considered when equipment and techniques are being selected for any excavation work that is going to be done. This article discusses some of the considerations that determine the method and cost of an excavation project.
The Type of Subsoil
Some form of geotechnical survey of the site is usually conducted prior to any excavation work. This survey is aimed at establishing the nature of the subsoil in the area so that an appropriate excavation method is selected. For instance, the existence of very soft soils can affect the decision to use of various techniques, such as shoring, to support the walls of the excavation.
Ground Water Conditions
The magnitude of the protection that is created at the excavation site is also affected by the ground water conditions at that specific site. For instance, locations with high water tables may call for the use of dewatering pumps as excavation works are going on. Alternatively, watertight sheet piling may be chosen in order to keep ground water from flooding the trenches or excavations that are being made.
The Surrounding Conditions
The vicinity of the proposed excavation site also exerts an influence on how the excavation will be done. For example, the presence of another building near the excavation site may prompt the excavation contractor to underpin the foundation of that adjacent building so that it doesn't collapse when the soil near it is disturbed by excavation works. Municipal drains may also need to first be diverted in case a survey finds that such drains are running through the proposed excavation site.
The size or scale of the excavation work that needs to be done greatly influences the techniques of excavation that will be used. For example, it may not be necessary to sequence excavation works in case the area to be excavated is small. Sequencing is usually necessary for several reasons, such as creating access for trucks and equipment that will be involved in the complex project. It may be hard to ferry excavation debris away from a site in case sequencing isn't done.
As you can see, the specific conditions pertaining to your project will determine how the excavation work is planned. The costs incurred will then be determined by those factors. It is therefore helpful for you to talk to several excavation contractors so that they explain the intricacies of your project before you set timelines for that work.