A complete reconstruction of the foundation system for any structure can be quite expensive. Thankfully, chemical grout injections are an effective and cost-efficient alternative technique that helps stop or reduce settlement. But what does this all mean exactly? Let’s explore chemical grouting injections further.
Introduction to Chemical Grouting
When a structure is founded on spread footings, it will likely settle due to loose-bearing soils. However, sometimes the presence of loose-bearing soils is not discovered during the pre-construction phase by the geotechnical analysis team, or it may be caused by incomplete subgrade preparation. In extreme instances, the structure can experience excessive settlement or complete foundation failure. This often happens after a seismic event, when loose granular soils undergo liquefaction. Therefore, when you have a structure founded on loose granular soils, chemical grouting helps provide long-term support.
How Does the Process of Chemical Grouting Work?
The process of chemical grouting is used to transform loose granular soils into sandstone-like masses. The process is also known as permeation grouting or pressure grouting. Chemical grout injections are used to fill cracks or extra spaces in soil and rocks. The injections permeate the loose granular soils with flowable, low-viscosity grouts that then solidify to create a cemented mass.
Chemical grout injections are made through a pre-drilled hole and flow under pressure through a sleeve port pipe where it permeates the soil and hardens. Once it hardens, the grouted soil is now stronger, less permeable, and stiffer, which helps to maintain the structure’s foundation.
Applications of Chemical Grout Injections
As mentioned, chemical grout injections help to underpin the foundation of a structure and are usually used on sands with low fine content. Overall, when chemical mixtures are injected into such soils, they improve soil stability and cohesion, boosting the soil bearing capacity.
However, chemical grout injections are used to underpin existing foundations and are also used to create support walls that make the excavation process safer. The process is also used to stabilize tunnel headings and create shutoff walls that prevent groundwater, dams, and landfill groundwater from seeping into a site under construction.
Other applications include reduction of soil erosion, prevention of soil settlement, and stabilization of slopes. During seismic events, loose granular soils have the potential to undergo liquefaction. So, chemical grouting is one effective way of ensuring this does not happen.
More Technical Details About the Chemical Grouting Process
Chemical grout injections are made through pipes referred to as Tube-a-manchette (TAM) pipes that deliver the grout into the soil.
The TAM pipes typically have injection ports along the length of the entire pipe, and the pipes have to be properly aligned to ensure the correct formation and stability of the grouted mass. The amount of chemical grout required to create the right amount of sandstone-like masses often depends on subsurface conditions.
Advantages of Chemical Grouting Injections
Chemical grout injections offer many advantages when it comes to stabilizing soils and slowing groundwater migration. The biggest advantage of chemical grouting is its cost-effectiveness. For instance, rather than the complete reconstruction of a foundation’s structure, all you need is a chemical mixture material that permeates the soil and forms immediate stone through granular soil. There’s no need for alternative and costly approaches, such as removal and replacement or piling.
Another advantage of chemical grouting is its flexibility. Chemical grouting has many applications, from underpinning existing foundations to providing excavation support. The procedure can easily be performed in areas where there is limited space. For instance, during excavation or when tunneling, chemical grouting enables the creation of support walls that ensure that both these procedures are less risky to the people performing them.
In addition, chemical grouting can be accomplished with minimal noise pollution and without disruption to the operations of the facility in question. Overall, chemical grouting boasts a design simplicity that makes this system advantageous in every way.
Where Can You Find Chemical Grouting Services?
There are many specialty contractors that provide chemical grouting services. However, you should note that it’s essential to perform a thorough geotechnical investigation before coming up with a chemical grouting program. For instance, you will need to ensure proper grout selection and injection hole geometry for the program to be a success.
Partnering with the right specialists is the best way to meet all your chemical grouting project needs, so contact us! We will provide you with all the information you need to know about our chemical grouting process, and we have all the right equipment to satisfy your chemical grouting needs.