4 REASONS NOT TO DRIVE SCREW PILES YOURSELF

Screw piles are suitable for constructing piers and docks, terraces, gazebos, bathhouses, and utility buildings. They have sufficient load-bearing capacity for frame and wooden residential buildings. And most importantly, they can be installed independently! No preliminary excavation work or heavy construction equipment required.

However, installation work requires adherence to technical regulations; failure to follow these regulations will reduce the stability, safety, and service life of the foundation.

TOP MOST COMMON MISTAKES made by amateurs when installing screw pile foundations:

1. FORGETTING ABOUT SOIL SURVEY

Without a comprehensive geological survey, it is impossible to calculate the optimal pile driving depth. To perform its function of transferring loads to soil layers with sufficient bearing capacity, a helical pile's blades must reach dense rock and penetrate the winter soil freezing level.

If the bottom of the pile becomes suspended in loose or water-saturated heaving layers, it will subside under the weight of the structure or be pushed out by the soil due to frost heave.

It is very difficult for a non-specialist to independently conduct an accurate survey and correctly interpret its results. Furthermore, laboratory testing of samples may be necessary to determine the bearing capacity of the soil. Without an understanding of the soil resistance at different depths, it is impossible to properly design and calculate the required number and diameter of supports.

To avoid compromising the viability of the structure before construction begins, it is best to commission geological surveys or test drilling from specialists who will provide a detailed report with a diagram of the strata and groundwater levels and soil bearing capacity coefficients for the correct selection of piles.

2. IMPROPERLY CONTROLLED THE INSTALLATION DEPTH

Driving piles based solely on the feeling of the tip "stopping" solid rock is a serious mistake, especially if a detailed soil study has not been conducted.

A professional approach is to mark the pile shaft with the estimated insertion depth, based on a geological study. During installation, the pile is driven until the mark aligns with the ground surface. However, even then, installers are not immune to the possibility of the pile starting to slip too early or, conversely, slipping deeper.

Experienced installers are able to quickly react to the behavior of the pile and screw pile machine during installation, while novice installers must resort to trial and error, which almost inevitably leads to additional costs for replacing damaged materials and reworking, often involving major capital expenditures.

3. IGNORE THE PILE FROM THE VERTICAL

The permissible deviation from the vertical axis during pile installation is no more than 2°. If the support falls further during screwing, fractures or cracks in the blade may occur. Exceeding the permissible deviation poses an equally significant risk to the entire structure: a support installed at an angle may fail to withstand the calculated loads and weaken the foundation.

Maintaining the vertical position of the pile during installation requires the efforts of a team of at least three people, one of whom is responsible for continuous visual and instrumental monitoring (using at least a magnetic level mounted on the shaft). During screwing, the support's position must be checked every two revolutions and adjusted if necessary.

4. DO NOT PROTECT THE PILE FROM CORROSION

Careful adherence to the instructions of engineers and the advice of professionals ensures a service life of the screw pile foundation comparable to that of a concrete foundation. Neglecting anti-corrosion measures can lead to a dangerous reduction in the durability of screw piles over several years.

As you can see, even a short list of basic requirements is impressive. It might be worth weighing the choice between assuming full responsibility yourself or contracting with a reputable company to perform the work.