Brief Description of a Helical Pier and its Uses
Helical piers are described as deep foundation underpinning elements, with the use of steel shafts together with helical flights. 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. For construction and repair or renovation works, this system is considered to be a proven system. Where the soil condition requires deep piles for installing foundation repair, this system is said to be a very effective solution. The helical system is proved to be advantageous over other systems especially if the work involves existing buildings.
Helical piers foundations need equipment that are just smaller, lighter and less specialized unlike the equipment used in other kinds of deep foundations. In this case, the cost of moving in and moving out or mobilization is usually lesser than other systems. Because of these features, the contractors can access to tight and confined areas to install helical piles versus the larger equipment which does not fit.
Helical piers are turned in with a torque motor like a wood screw being turned into a piece of wood, and this makes helical piles vibration free when installed that gives it an advantage. Be aware that it is not wise to add structures on an existing structures close by.
The torque of each helical pier should be continuously monitored by the contractor during installation of the helicals. Because the capacity of each pier is directly related to the torque rating, the contractor will know the load or capacity that each pier can support.
After installation, there is no curing time in the case of helical piers installation. Minimal excavation will suffice in a helical pile because it is turned or screwed in. Costs of removal and disposal are saved when installing the piers because there are not spoils to be hauled or removed from the area of construction.
There is not violent hammering or banging to install helical piers and this is a big advantage with regards to the reduction of noise.
Those existing foundations that are failing, can be solved using helical piers, and this is another very important advantage of helical piers, aside from being used in new constructions. Contractors also use the helical piers under the existing foundation, rather than remove and disposal it in a landfill, and when this is done, there is a deep foundation system that is created contributing to the 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.