Soils that have poor load-bearing capacity threaten the stability of structures whose weight the soil is meant to support during foundation repairs. In efforts to look for solutions to this challenge, you seek the opinion of different piling contractors.
One suggests that steel piles would be the best for the job, while the other suggests concrete piles for the same job. Here are two things the contractor advocating for concrete piles will likely mention.
Rust Is a Non-Issue
As the contractor who advocates for concrete piles defends their choice, he or she is likely to mention that concrete piles are advantageous over steel piles because they won't corrode and rust. In this regard, the contractor claims that concrete piles are likely to outlast their steel counterparts should all other factors remain constant.
Concrete piles are often preferred for their high structural strength. Part of this strength is derived from the infusion of steel reinforcement bars into the internal structure of each concrete pile. Steel reinforcement bars in concrete piles are as susceptible to corrosion.
In order to increase the corrosion resistance of the material, the steel reinforcement bars are made of high- carbon steels known for their superior resistance to the corrosive effect of exposure to air and water.
Cost Vs. Quality
It's also likely that the contractor advocating for concrete piles will mention the possibility of cutting on project costs by having concrete piles poured and cured on-site. This is referred to as 'in-situ' casting. Steel piles are fabricated off-site before they're transported to the site ready for installation.
In-situ casting eliminates the need to transport concrete piles from their point of manufacture or sale. This is a significant advantage considering how heavy concrete piles are and considering that the cost of transportation is directly proportional to the weight and quantity of piles.
But at what cost do the 'transportation' savings come? Pre-cast concrete piles are made off-site where piling contractors have greater control over the quality of the finished product. Thus, pre-cast concrete piles are less likely to have structural defects (e.g. brittleness and porosity) than piles cast 'in-situ'.
If you choose to settle for quality (pre-cast piles) over cost (in-situ cast piles), there are no major savings to be made with respect to pile transportation.
Different types of piles have unique advantages over each other in different situations. Because there's no perfect pile material, it's all about making trade-offs.