Carrying Out Construction Work

Posted on: 13 March 2018

Engineers usually conduct several surveys, such as hydrological and soil structure surveys that confirm that the subsoil at a proposed construction site will be able to withstand the loads that will be placed upon it. Several measures can be taken to strengthen soil that has been found to have a high risk of liquefaction. This article discusses some of those measures.

Mechanical Compaction

One of the options that is available to design engineers involves compacting the loose soil using compaction tools. For example, a vibratory compactor can be driven over the soil until the particles become packed together densely. Alternatively, compaction piles can be driven into the soil beneath the planned foundation so that the piles hold that loose soil within a confined space. Other compaction techniques, such as vibro-floatation and blasting can also be considered if the specific site conditions make them a better option.

Chemical Stabilisation and Grouting

The engineering team can also consider stabilising the loose soil using chemicals. For example, lime can be mixed into the soil so that the soil forms a hard layer which will not shift or settle easily. Cement stabilisation is a stronger alternative to lime stabilisation in case engineers determine that more aggressive stabilisation techniques are called for at the site. Grouting may be selected due to its cost-effectiveness when compared with lime or cement stabilisation. Grouting entails injecting special compounds into selected sections of the soil. These compounds react with the soil and harden into a substance that will hold the soil firmly so that it doesn't move easily.

Water Table Management

Liquefaction can also be prevented by managing the water table at the proposed construction site. This process entails installing drainage pipes on the perimeter of the planned foundation. Those pipes will then remove water from higher up in the soil structure and transport it deeper into the earth's crust. Such a measure can reduce the amount of water that is readily available to disturb the foundation. An additional benefit is that the water extracted can recharge the aquifers from which water can be pumped for use by the occupants of the building.

The methods above can be used even in earthquake-prone locations. The key to the success of the system selected lies in the civil engineer conducting comprehensive tests that reveal the magnitude of the liquefaction risk. Do your part by selecting an experienced engineer. Give that expert the necessary resources so that he or she designs the best way to strengthen the foundation of the proposed building.

For more information on civil engineering, contact a professional.