The integrity of your entire building primarily depends on the foundation used in its construction. There are many types of foundation systems, but helical piers or piles are the most commonly used for deep foundations.
They are quick to install, result in minimal site damage and have an enhanced load bearing capacity. Helical piers can also be used in multiple soil types and profile depths.
There are many categories of helical pier designs that foundation contractors might recommend for your building’s foundation construction or repair. Here are the three common ones.
Solid Square Shafts
These are square shafts that are continuous at both extensions and carry a structure’s load through the end of the helical pile.
Solid square shafts can hold large axial compressive loads and are generally used in tension applications more so hard and rocky soils. The shafts are however narrow and might buckle in soft soils when supporting lateral loads.
Round Shaft Piles
A round shaft helical pile has a broader diameter compared to the square shaft design. It hence provides better structural capacity for lateral loading and soft soils where buckling is a concern.
Round shaft pipes can also be grout-filled to enhance their structural capacity. They are however hard to install in rocky and hard grounds.
Round and Square Shaft Combined Piles
These are primarily used in places where hard rock is located under a soft surface soil, grout-restricted sites and areas with high water tables.
Round and square shaft combined piles have exceptional penetrating characteristics and resist lateral loads and buckling. They are however costly and hence used in only particular cases.
There are several variables your contractor will consider making an educated choice from these options. It would thus be best if you worked with a conversant contractor to ensure your property has the best and most durable foundation.