Underpinning plays an important role in supporting, strengthening and maintaining the foundation of a structure. Nowadays, this construction technique is not only used as a preventative method but also as a measure to fix foundation issues. There are many types of underpinning methods available in the construction world today. To know more about them, keep reading.
Types of Underpinning Methods
- Mass Concrete Underpinning
Mass Concrete Underpinning, often known as the pit method, is a traditional process that dates back hundreds of years. It entails gradually extending the existing foundation until a stable stratum is reached. The controlled excavation, done in stages or pins, exposes the soil beneath.
The excavation is filled with concrete when the necessary strata have been exposed, allowing for curing before the following stage. Dry sand-cement packs are inserted through an extra pin to transmit the load from the old foundation to the new one. Although this practical approach works for shallow foundations, more complicated foundation problems can call for other strategies.
- Mini-Pile Underpinning
Ideal for variable ground conditions and limited foundation access, mini-pile underpinning involves transferring loads to stable ground at considerable depths. The installation of mini-piles requires specialized equipment and skills, making it a technically involved process. Advantages of this underpinning method include it being cost-efficient, easy to handle and easy to transfer.
- Piled Raft Underpinning
Designed for comprehensive underpinning needs, this method replaces internal floors with piles arranged in a grid pattern. A concrete raft is then placed over the piles, offering both the benefits of mass concrete and the added support of mini-piling.
- Pile Method of Underpinning
This method employs piles on adjacent sides of weak foundations, linked by needles or pins. It addresses soil settlement due to factors like waterlogging or clay content, providing stability and reinforcement.
- Pre-test Method of Underpinning
Effective for pad or strip foundations, this method involves compacting and compressing subsoil before the underpinning process. Reduced noise and disruption are advantages of this approach, which is suitable for a certain range of stories.
- Pier and Beam Underpinning Method
Developed post-World War II, this method accommodates situations where traditional mass concrete underpinning isn’t optimal for deeper foundations. Reinforced concrete beams distribute loads to mass concrete bases or piers, adapting to different ground conditions and applied loads. This method is also known as the beam and base underpinning method.
Which Method is the Best For You?
Each approach brings its own set of advantages and limitations. Determining the optimal method for your structure involves a thoughtful analysis of several crucial factors:
- Budget: Understanding the financial scope of your project is paramount. Different methods come with varying costs, and aligning them with your budget is essential.
- Topography: The lay of the land plays a vital role in selecting the right underpinning method. The geological characteristics of your site influence the feasibility and effectiveness of each technique.
- Transportation: The ease of transporting materials and equipment to your site should be considered. Some methods might require heavy machinery, affecting accessibility and costs.
- Chosen Underpinning Services: Collaborating with reputable underpinning services is key. Their expertise can guide you in selecting the method that best suits your project’s needs.
- Timeline: The time required for underpinning can impact project schedules. Depending on the urgency of your project, certain methods might be more suitable than others.
Engaging professional underpinning services can prove invaluable in this decision-making process. Their insights and evaluations can help determine the most appropriate method tailored to your structure’s requirements. It is surely an investment that can prove to be lubricious in the long term.
You can rely on Atlas Piling and Drilling Inc. for the best underpinning services in BC (British Columbia). With an extensively skilled team, they possess the vital experience, skill and technical expertise to make foundation-underpinning systems with utmost reliability and safety.