Foundation Problems Resulting from Expansive Earth.
Expansive clay soils exist in several areas of the nation, including Texas. This kind of soil shrinks and cracks when it dries out. When it rains, soils with high clay and silt content don’t allow water to pass through the soil. Instead, water is absorbed and held in the soil, significantly increasing its volume.
Soil and water pressure may cause foundation problems
It’s difficult to imagine that soil may damage a product as hard, dense and strong as concrete, but homeowners and foundation repair contractors alike will testify to the destructive power of expansive soils.
So which kind of damage can occur as a result of expansive soils, and how can it be repaired and/or avoided?
Cracked and buckled walls probably occur more often as a result of expansive soils than other foundation problems. During a dried spell, clay-rich soil will probably pull away from a basis wall, creating a space that could fill with stone, gravel, loose soil and other debris. Some homeowners even deliberately complete this shrinkage gap. Nothing bad happens until there’s a lengthy, soaking rain caracteristicas de la losa de cimentacion. Then the excess material in the crack increases stress on the foundation wall since the soil expands. Since there’s not really a balancing volume of expansive soil against the within of the wall, this one-sided pressure can push the wall inward, causing it to crack and bow in sections. Occasionally the foundation wall will resist cracking or bowing, but the damage will take the shape of tilting. The top of the wall will soon be pushed in by the expansive soil, creating a basis that tilts inward.
Soil that shrinks, settles and expands causes slabs, footings and walls to crack
Other site conditions that could subscribe to foundation problems associated with expansive soils include trees and bushes that displace soil or increase drying and shrinkage by absorbing ground water. Soils full of clay and silt aren’t just unstable; they also have poor load-bearing characteristics compared to soils which contain sand and gravel. Foundation footings and slabs built on clay-rich soil can heave in response to wet conditions or settle as a result of excessive shrinkage. In any case, cracks in foundation slabs, footings and walls will likely accompany heaving and settlement, since concrete can’t stretch or bend.
Foundation repair contractors overcome soil issues with special tools, materials and techniques
To a homeowner, the sort of foundation damage stated earlier looks severe. But an experienced foundation repair contractor sees a chance to stabilize difficult soil and connect the building foundation to solid, stable soil at greater depth.
Different techniques can be used stabilize the soil that surrounds a home or commercial building. Since water is why is clay-rich soil swell and shrink, among the first things foundation repair contractors do is to check the big event of gutters, downspouts and general drainage round the house. Moving water from the foundation is just a reliable solution to limit soil movement, protecting the foundation from soil’s expansive pressure.
If the soil has shrunk or settled, inducing the masonry to crack and sink, soil stabilization is sometimes accomplished by driving helical piers to the soil. The helical flanges (or plates) on these steel piers are shaped just like the threads on a wood screw, and function in the same way. Because the contractor turns the shank of the pier, the helical plates pull the pier deeper to the soil. The contractor will add pier sections to be able to reach stable soil under the damaged foundation. Once the pier’s resistance to rotation reaches a predetermined level, the contractor knows that the pier is solidly anchored, and can provide the stable support the foundation has been lacking. A bracket is installed to connect the pier to the foundation; this could also enable the contractor to lift a sunken slab, footing or wall back again to its original position.