What are the Uses of Helical Piers?
Deep foundation of underpinning elements that are constructed using steel shafts with helical flights are known as helical piers. In performing the construction, shafts are moved to a bearing depth by twisting them into the soil, and at the same time the torque is monitored to the pile capacity.
The technology of helical pier is over 100 years old. Considered to be proven for new constructions and repairs or renovation works, this system is well used. Where the soil condition requires deep piles for installing foundation repair, this system is said to be a very effective solution. Helical piers as compared to other systems will prove to be more advantageous especially if the work involves existing buildings.
Unlike deep foundations that require more specialized equipment, in the helical piers, the equipment used are usually smaller, lighter and less specialized. With these conditions, the cost of mobilization or the move in and move out, is generally lower compared to the other systems. These conditions allow contractors then to go in tight or confined areas in helical piles installation as compared to the larger equipment which cannot fit into the area.
Helical piers are also advantageous in the sense that they are installed vibration free because they are turned in with a torques motor similar to a wood screw that is turned into a piece of wood. Be aware that it is not wise to add structures on an existing structures close by.
It is advisable for the contractor to be monitoring the torque it is required when installing each helical pier. The capacity of each pier is directly related to the torque rating, therefore the contractor will know at the end of each installation the load or capacity that a pier can support.
Helical piers installation does not require curing after installation and they can immediately be loaded. Also, there is minimal excavation required for helical piers that are turned on or screwed in. Another advantage of helical piers is that you save on costs of removal and disposal because there are not spoils to be removed from the site.
Noise pollution is drastically lowered when helical piers are installed because of the use of smaller installation equipment that do not require violent hammering or banging.
There is another very important advantage of using helical piers and that is they are great solution to projects with existing foundation that failed, on top of being used for new construction projects. Instead of removing the present foundation that failed and dispose it in a landfill, the helical piers are used over the present foundation, thereby creating a deep foundation system plus contributes to a green environment.
Since there are differences in any project, it is advisable to contact structural engineers to see what is the right method for your project.
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