Structural Foundation Design & Repair
Structural Foundation Types
PSE Consulting Engineers, Inc. can provide foundation design for any type of structure, from a small shed to a large industrial warehouse. Our talented team will design your foundation for what is most appropriate, taking into consideration your wants, the project’s needs, and the site’s soil conditions.
Types of Foundations
There are two major types of foundation categories – shallow foundations and deep foundations. Each category has its own foundation design type as well as application.
We will explore the features and differences of each one below.
This foundation type is useful for situations where the shallow soil can support the loads caused by structures above it. Most of the time, these foundations are wider than they are deep.
- Strip Footing –Strip footing is also known as a continuous footing. This type of foundation consists of a row of columns in which each column is spaced near one another. Strip footing is a much more efficient and economical choice than a spread footing.
- Spread or Isolated Footing –Spread or isolated footing, also known as a pad footing, is used when supporting an individual column. This type of footing can be designed as a rectangular slab of the same thickness, a square, or a circle. It may also have a step-like design to help distribute the load over a larger area.
- Combined Footing – This type of footing is used when two columns are close together, and their individual footings would ultimately run into each other or cause an overlap.
- Strap/ Cantilever Footing – This type of footing is consists of two individual footings that are connected with a lever or structural strap of various types. This allows the two bases to behave as one. This design is used and is more economical than a combined footing when the distance between the columns is large, and the soil pressure allows.
- Mat or Raft Foundations –Also known as a slab foundation, this type of foundation exists under the majority of the structure, providing support.
This foundation type is used when the soil is weak, and is easily compressed. Typically, there is much stronger soil at a lower depth. Deep foundations may be used for functionality as well.
- Basement Foundation –This type of foundation provides a hollow substructure to allow space below ground level, primarily used for work or storage space.
- Caissons Foundations –This foundation is constructed by drilling a large hole in the soil, often down to a harder soil or rock, which is then filled with concrete. Sometimes, the base of the caisson will be bell-shaped to decrease contact pressure or soil pressure; these are considered belled caissons.
- Pile Foundations – This foundation usually consists of long and slender members constructed by driving the members down to the correct foundation level. Sometimes this may be done by drilling tubes to the desired depth and then filling them with concrete before or during the removal of the tubes.
PSE Consulting Engineers, Inc. can provide the initial inspection and report for any type of foundation. Our team will also be able to offer solutions to help fix some of the common problems often associated with foundations.
Most problems with a home occur when a foundation is constructed improperly, such as not allowing the footing to cure sufficiently before building. However, problems can also come about over time. This can be due to weather and/or geological changes. Some of the signs that you may have foundation problems are:
- Cracks in the interior walls
- Separations between concrete blocks (block foundations)
- Cracks or crumbling of concrete
- Doors that will not close properly
- Bulging floors
Foundation problems can also be caused by excessive water damage and excessive structural movement caused by high winds. A foundation or footing that is not constructed below the frost level could cause serious long-term damage due to the soil expanding and contracting with the change from warmer – to freezing weather.
Repairing Foundation Damage
You should always seek the help of a professional when you see warning signs of foundation damage. Your best bet is always to hire a structural engineer, as they will be able to provide a findings report and possible solutions for the existing damage. Some damage may only be cosmetic and could be repaired by the homeowner. Other damage may be affecting the load-bearing capability of the foundation and poses measurable risk. This should be taken seriously and will need to be looked at and repaired by a professional contractor using the information provided by the Engineer’s inspection. Keep in mind that depending on the extent of the damage and your foundation type, it may also be beyond repair.
Site conditions and geographic area will significantly impact the options for repair that will be available. Some of the most popular repair options are:
- Steel Piers – This option has revolutionized the way we repair foundation damage. Steel piers take significantly less time to install and require much less landscape to be touched than traditional concrete piers.
- Helical Piers – Helical piers are primarily used for light-loaded areas, such as deck columns. These piers work best with exterior foundation repair as well as slab repairs. This has also become an excellent method for new construction with areas having poor soil conditions as well as for repairs.
- Concrete Piers – This is the most expensive type of foundation repair due to the amount of work involved to be successful. However, it can be a permanent fix and the most effective of the options.
- Polyurethane Foam (High Density) – This is used to repair slab foundations and has made this task much easier in many instances. The process is simple. The foam is injected into and around the problem area to fix what cracking or damage that has occurred. Plumbing tests are a must before exercising this option to ensure there are no leaks in the main supply or drain lines. You will also need to be aware of where the HVAC ducts are located in your home to avoid clogging them up.
Contact Us for Foundation Design & Repair
Our past and repeat clients love the services they receive from PSE Consulting Engineers, inc. We are a leader in sustainable engineering practices and can provide you with the foundation design and repair you need to complete a successful and safe project. Visit our FAQs for more information, and then contact us to request a quote on your foundation design and repair projects.