Pyrite and pyrrhotite are minerals known as iron sulfides. When iron sulfides are exposed to water and oxygen, a series of chemical reactions break down the iron sulfides and forms new minerals called sulfates. These sulfates take up more space than the original iron sulfides. As they grow, the new sulfate minerals push against the surrounding rock, causing it to swell and crack. This causes damage in two main ways:
- If pyrite or pyrrhotite are present in the rocks underneath buildings, the swelling can push on the foundation, walls, and basement floor of the building, causing cracks and other structural damage. In some cases, groundwater can then transport sulfates into the cracked foundation, causing further damage.
- If pyrite or pyrrhotite are present in the aggregate material used to make concrete, the building material itself can be compromised. If water and air get into the concrete through small cracks and holes, the iron sulfides inside can begin to break down, cracking the concrete and allowing more air and water in, causing even more damage. This is a particular problem for concrete foundations and basements when water seeps in from the surrounding ground.
An Inclusive Guide to Hire the Best Building Contractor
A house doesn’t count on the list of things that aren’t required to be owned. A house is, in fact, a lifetime investment. However, taking on a job yourself can rather be a risky affair, especially when it comes to moving or building a house. Hence finding a proper contractor to build your dream home is much a necessity. While there are multiple building contractors available in the market, choosing the wrong option would all the more create difficulties. It might lead to delays alongside legal problems too. A professional contractor must come with below-offered qualities.
A Professional Contractor has the License to Work in the Area
Having insurance and a license can demonstrate a professional contractor’s knowledge and credibility. A license can minimize the risk to the homeowners of getting ripped off. If the contractor doesn’t come with insurance or license, hiring him would be of no use. Instead, picking a contractor who can specialize in the project type is beneficial.
A Detailed Contract Ahead of Hiring
The contract must cover the brands, costs, including start and finish dates. Another important thing to pay attention to is pyrite or pyrrhotite problems. These are minerals familiar as iron sulfides. When exposed to oxygen or water, the breaking down of iron sulfides occurs through a series of chemical reactions. It either pushes on the building foundation or building materials are compromised. Hence, one must also attain more details on pyrrhotite problems, in case you live in Connecticut.
In addition to the aforementioned things, one must also look for work samples of the contractors. Finding a professional contractor might be a taxing affair. But with the aforementioned things kept in mind, one can proceed effectively. Choosing a professional contractor would thus make your house building affair seamless.
One such issue has been making headlines since at least 2010 in the state of Connecticut, pertaining to an expansive reaction of a specific, identifiable aggregate. A decade earlier, similar issues were identified in Quebec, and documented cases have occurred in many European countries. This article presents information surrounding the expansive reaction related to an iron-sulfide-containing aggregate called pyrrhotite.
Pyrrhotite is the suspected cause of concrete durability issues found in the northeast U.S. (Conn.), primarily used for residential foundations. The foundations of interest are experiencing a slow crack development, resulting in the eventual loss of concrete strength. The problems, sometimes exhibiting themselves within the first 10 years, often begin to show after 15 to 20 years or longer. Presently, the only known repair for the damaged foundations is the removal and replacement of the affected concrete.
For many reasons, the number of homes affected is unclear, but the problem has only been identified in four of the eight counties in Connecticut and in the Trois Rivieres area of Quebec, Canada. Homeowners in these areas are concerned and looking for assistance. Several concrete industry professionals are studying the issue to develop appropriate guidance. Meeting during conventions of the American Concrete Institute (ACI), participants from several committees impacted by the issue, and research organizations offer their extensive knowledge of concrete and background in the production and construction of these systems. Together they are well suited to add some understanding to this issue.
Ref: //www.americangeosciences.org/, //cfawalls.org/