Drilled Shaft Construction: Is It Necessary?

Planning a big construction project, be it commercial or a public works undertaking, often begins underground long before work above the earth’s surface can begin. For those who haven’t walked a project through to fruition before, the realization that specific underground site work is critical to overall success may come as a bit of a surprise. When construction designers are requesting retaining walls or drill shaft features, however, they’re not trying to bilk a project budget. Instead, they are taking the right measures to ensure safe construction and operation down the road.

For the layperson, a drilled shaft is somewhat like a well that is bored straight into the earth. These cylindrical construction features are designed to provide support for what will be built on top of them. Shafts are drilled straight down and are generally filled with concrete or another retaining tool. These shafts are typically created at regular intervals of each other. The idea is to create a solid foundation on which to build. This type of retaining construction is often critical for especially tall structures, such as towers, bridges, tanks and some buildings. The design provides foundational support when it is needed and lends stability to the overall construction process.

Retaining walls might also be recommended in projects where soil stability is a concern. This is a typical inclusion when basements, for example, are in the design. Retaining walls help hold soil in place to create an excavation space that is safe from the possibility of cave in. They may also be used, in different forms, to prevent soil erosion in areas where this is a major concern.

Not sure if your project needs the extra support of a drilled shaft design or retaining walls? Here’s how to find out for sure:

• Work closely with the project engineer to go over site specifics
• Consider the height of the eventual construction and the weight of the proposed structure
• Pay attention to soil stability on the site
• Consider the water table level; if it’s high, some remediation might be necessary even for a smaller undertaking

Drill shaft construction and retaining walls aren’t an unnecessary extra expense. These structures provide stability for what is yet to come. When project designers request these features, there’s generally good reasons backing up the need. If long-term site stability matters, construction may indeed need to begin below ground.

About the Company

DMI Drilling is a leading excavation and drilling company in Washington. Providing drilled shaft construction, retaining walls and other earth stabilizing techniques, the firm helps its clients begin their projects on solid ground.

DMI Drilling Construction has been providing retaining wall services to clients across Washington State since 1991.