Vibro stone columns offer general contractors in the State of Florida, a more sustainable and economical alternative for solid commercial deep foundations as opposed to deep and piling foundation solutions. They are designed with complex engineering techniques and bypass many ground issues by strengthening and densifying weak compacted soils in-situ.
Vibro stone columns can be used to increase the bearing capacity of fills and in-situ soils while reducing the different settlements that occur in compressible and non-homogeneous soils. This allows general contractors to use thinner slabs and shallow footings for in-situ and loose granular soils. Additionally, they can be installed in locations where deep foundations and piling applications for commercial buildings can be difficult at best
Water Tables in Florida
Since the State of Florida is subjected to water tables combined with an influx of heavy tropical downpours, many commercial buildings and multi-story complexes constructed on concrete slabs depend on Vibro stone columns for support. Some of the cities where vibro stone columns are currently being installed today include:
• Ft. Myers
• St. Petersburg
Vibro Stone Columns Installation
Vibro stone columns (VSC) are typically installed on-site by professional ground improvement companies trained and experienced at these types of structural aggregate support installations. A certified technician then deploys a vibrator to its target depth, which results in a cavity filled with inert hard stone, free of silt and clay fines. As the stone infills, it is then compacted in varying stages until each stage reaches bearing capacity.
Below are three conventional methods of VSC installation available to general contractors in Florida:
- Basic Method
The basic method involves a vibrating poker called a vibroflot, which is attached to a vibropiling rig that is specifically designed to penetrate the ground. The vibroflot’s own mass supplies the power for penetration coupled with a pull-down mechanism on the rig that flushes pressurized air, providing solid and accurate installs. Most expert soil remediation companies utilize a computerized system that monitors the VSC installation and warns the operator of any problems during pre-soil construction.
- Top Feed Method
Once the target depth has been reached when deploying the top feed method, the vibroflot is extracted while charges of stone aggregate are poured from the surface into the borehole. Next, the vibroflot is re-inserted into the borehole as it compacts stones into in-situ and surrounding soils. In loose granular soils, the vibratory effect provides significant improvements in ground density, making them the ideal solution for structural stability and foundation support.
In cohesive soils, vibro stone columns provide a drainage route for excessive pore water and serve as reinforcement, which also speeds up the consolidation times. Additionally, you can expect improvements in your bearing capacity as well as normal settlement characteristics with the top feed method for proper soil reinforcement and load-bearing concrete slab construction.
- Bottom Feed Method
The bottom feed method is certainly effective in cities such as Tampa, Naples, and Miami, where high water tables and weak soils are present. High water tables can collapse the bore hole when the vibroflot is extracted; therefore, the bottom feed method is often utilized in cities with high water tables and in-situ soils. This purpose-built design ensures the structural integrity of the VSC from top to bottom.
The bottom feed method primarily works via fitted hopper attached to the vibro rig that feeds aggregate stones down a tremie pipe, which runs the length of the vibroflot. The compaction and reinforcing action of the VSCs results in a dramatic improvement in ground characteristics and load-bearing capacity. For proper commercial foundation support, VSCs play an important role in solid concrete foundations.
VSCs Provide Solid Commercial Foundations
Vibro replacement stone columns are ideal for industrial facilities or commercial multi-story buildings being constructed on in-situ soils throughout Florida. If you’re a general contractor under contract to construct structures such as shopping malls, big box stores, or commercial skyscrapers in the State of Florida where loose granular soils are present, it is highly recommended to consult with a ground improvement contractor for proper soil inspection and corrective support analysis.
Failure to do so can result in expensive foundation and structure repairs as well as the potential of being faced with several civil lawsuits. You can avoid such things by installing vibro stone columns before pouring your commercial foundation in loose granular soils and at other known locations where high-water tables are present such as Orlando and Clearwater. VSCs provide solid commercial foundations and eliminates your worse settlement nightmares as a general contractor.
The Advantages of Vibro Stone Columns
As a general contractor in the State of Florida, you should consider the advantages of VSCs if you have not done so already. VSCs are significant when it comes to present cohesive soils, and due to the engineering design of VSCs, they can be sorted to accommodate a wide range of soil types and configured with varying load combinations as well as different settlement thresholds.
When it comes to innovative and high-tech soil reinforcement applications for commercial foundation support, VSCs are the hottest application currently being installed throughout Florida and best of all, they provide plenty of staying power, making them something every commercial builder should never go without considering.
One distinct advantage is that in most VSC applications, the column spacing ranges between 1.2-2m underneath the main load-bearing foundations, but they can go as deep as 3m beneath concrete commercial floor slabs, making them ideal supports for foundations constructed on in-situ and loose granular soils.
This method is equally suitable for the improvement of soft soils commonly found throughout Florida such as clays, silty sand, silts, and non-homogeneous fills; however, this advanced technology is not suitable for very soft clays, peat, and organic soils due to their deficiency of lateral confinement. When constructing concrete commercial slabs on soils such as these, other ground improvement applications should be considered.
Here are some more advantages of VSCs:
• Mitigates the risk of liquefaction
• Expedites consolidation settlement
• Differential settlements and reduced total
• Increased bearing capacity
Solid commercial foundation VSC applications include the following, but are not limited to:
• Road & rail embankments
• Reinforced soil retaining walls
• Industrial & commercial foundations
• Multi-story buildings up to four stories
The Benefits of Hiring an Expert VSC Installer in Florida
There are several benefits that general contractors can experience when hiring an expert VSC installer in the State of Florida. Professional ground improvement companies provide expert soil analysis and the recommended vibro stone application for your specific application’s blueprint design. The biggest benefit of hiring a ground improvement company experienced in VSC installations is they come with all of the necessary drill rigs, boring equipment required for proper VSC installation, and have experience with the in-situ soils in your area.
To schedule an appointment with a ground improvement expert in your local area, please call Helicon today at 813-567-1065 or simply fill out our online contact form to get expert advice and bullet-proof vibro stone columns installations. We also offer on-site consultations and soil analysis tests, ensuring your commercial structure starts on a solid foundation but ends with a professionally-installed Helicon VSC installation coupled with guided assistance throughout your commercial foundation project with guaranteed results set in vibro stone columns.