Sites with poor soil quality are a consistent issue for developers and general contractors. Sites today have urban fill, undocumented fill or possibly even organics that need to be dealt with to get the proper bearing pressure and settlement criteria for a building.
So, what are the best methods for soil improvement for construction? Learn more about the properties of unsuitable soils and the ground improvement solutions provided by CNC Foundations in today’s blog.
All soil is made of air, water, plant materials, organic matter, and minerals. Man-made activity or natural geological processes affect a soil’s suitability for foundation support of a building. For example, fill material without documentation of compaction placement, organic material, or soft and normally consolidated material can all subject a structural to excessive settlement or bearing capacity failures.
Ground improvement solutions are used when a geotechnical engineer determines the soil quality to be poor.
Soil removal and replacement removes unsuitable soil from below a building’s foundations and/or slabs and replaces the material with compacted cohesive or granular fill material that is capable of supporting the structure.
While soil removal and replacement is an effective ground improvement technique in some cases, it does create a few problems on a worksite. Some of the disadvantages of soil removal and replacement include:
Using a professional service to remove soil costs up to $105 per hour. Some of the factors that determine the overall cost are:
- Depth of unsuitable material
- Disposal of unsuitable soil and importing new fill material from a borrow site
- Presence of high water table
- Presence of adjacent structures that would necessitate an underpinning/shoring system
Soil removal and replacement can be a time-consuming process and can cause delays in the construction schedule depending on the factors discussed above.
Vibro stone columns (VSCs) are a versatile ground improvement solution that reduces project schedule and cost without sacrificing quality. VSCs are dense columns of aggregate installed through unsuitable soil to densify and reinforce the soil strata.
A vibroflot is driven into the ground with a purpose-built installation rig, and the column is created by inserting granular material into the boreholes and compacting the aggregate in lifts throughout the unsuitable soil. .
VSCs are a popular ground improvement solution because they can be applied to a wide variety of projects and offer several benefits, including:
By increasing the soil’s strength through soil densification and reinforcement, VSCs increase bearing capacity.
VSCs stiffen the ground matrix and reduce compressibility by reinforcing the existing soil.
Engineers can install VSCs in a grid pattern to reduce the potential for liquefaction in earthquake-prone areas.
VSCs offer quick installation times without the uncertainty of how deep f removal and replacement will be required. They’re especially ideal for projects that are under strict deadlines.
CNC Foundations offers specialized ground improvement services for clients across various industries, with the most effective design and implementation processes. Contact us today if you’re looking to partner with a company that provides first-rate ground improvement solutions.