Geotechnical engineers constantly search for the best water control methods for their projects. While the focus is often on water infiltration, leading to water sealing and waterproofing solutions, the starting point is always soil improvement, which commonly supports water control efforts.
This article examines the numerous soil improvement grouting techniques, water infiltration solutions, waterproofing approaches, and water sealing technologies.
Grouting is a soil improvement technique that enhances soil cohesion, strength, and stability. Grouting involves injecting agents into the soil to fill voids, compact the ground, and mitigate soil settlement. There are six main types of grouting.
Cementitious Grouting. This type of grouting uses a mixture of cement and water plus additives that enhance flow or accelerate curing. Grout pumps force the grout into boreholes at specific locations and depths. The grout fills voids and fractures to increase the soil strength. It can also be used to create barriers to water flow to prevent erosion and seepage.
Bentonite Grouting. Rather than cement or chemicals, bentonite is a clay that swells in contact with water to form a gel-like substance. It uses boreholes and pumps to inject a bentonite powder and water slurry. It controls water flow by sealing and stabilizing the soil. It has excellent sealing properties and is compatible with many types of soil.
Compaction Grouting. This form of grouting uses closely spaced injection holes and high-pressure pumps. The grout, consisting of cement, sand, and water, displaces and compacts the soil. That increases the soil’s density, reduces settlement, enhances structural support, and improves its load-bearing capacity.
Jet Grouting. With jet grouting, high-velocity jets inject a mixture of cement, water, and additives as needed. Depending on the project’s soil improvement requirements and soil type, it can use several methods, including single, double, or triple fluid. The jet grouting process creates a soil-cement column that can provide soil stabilization, excavation support, and groundwater control.
Permeation Grouting. Permeation grouting injects a low-viscosity grout that permeates the soil and solidifies, thereby improving soil cohesion, reducing permeability, and preventing erosion. It is an ideal water-sealing technology for underground structures. It can also be used with tunnels to reduce the risk of settlement and collapse.
Fracture Grouting. This type of grouting is used to seal fractures and fissures in rock formations, preventing water flow. Boreholes are drilled in the rock, followed by injection of the grout that flows into the fractures. The grout then solidifies, forming an impermeable barrier to the water and strengthening the rock formation. It is used in tunneling, underground mining, dam rehabilitation, and rock stabilization.
The soil improvement grouting approaches shown above are also used for pre-tunnelling waterproofing. Pre-tunnelling waterproofing uses a very finely-grained cementitious grout pumped into the rock roughly 20 to 30 meters ahead of the tunneling. As the tunnel or mine is advanced, the grouting moves ahead of the excavation to seal the ground and stop water from entering the tunnel. Pre-tunnelling waterproofing is also an excellent application for our NOH2O® polymer-based emulsion grout.
Sovereign uses specially designed systems and techniques for each situation. The very small particulates in the NOH2O® emulsion seal every penetrated crack and fracture in the rock to effectively waterproof the tunnel, including when faced with high pressures as encountered in deep subsurface mines. Click here to learn more about NOH2O® and how it could help you.
Grouting can further be used in post-construction water sealing and waterproofing. Our post-construction waterproofing can also be used in ground improvement projects by injecting grout into the soil or creating soil-cement columns, which increase soil cohesion and stability – and overall contributes to soil improvement.
Jet grouting, in particular, creates impermeable barriers to control groundwater flow and prevent seepage. This is particularly beneficial in projects where waterproofing is crucial, such as when constructing tunnels, underground structures, or in mining applications. Read here for more on escaping water and how we can help you minimize the risk of unwanted water intrusion.
Further applications of post-construction waterproofing using jet-grouting soil-cement columns include retaining walls where traditional approaches won’t work, slope stabilization – preventing soil movement and erosion, foundation support or reinforcement, and permanent or temporary excavation support.
Another type of water sealing technology is negative-side injection. Negative-side injection involves waterproofing material being applied to the opposite side of a wall or surface in direct contact with water. It is often a suitable solution when excavation is not possible or cost prohibitive. The applications of negative-side injection include basements, lift pits, tunnels, retaining walls, and ceilings.
We began our 50+ year history through water control in mines using our patented NOH2O® polymer-based emulsion grout products to address high pressure, high in-flow rate water ingress. These products result from years of development by our dedicated research team, who are focused on continuously innovating new water sealing technologies for tomorrow’s civil, mining, and energy challenges. For more on how we control water in mines, read about our mining services here.
We bring that same expertise and experience from water control in mines to all we do, including providing the best soil improvement geotechnical engineering solutions. If you require further information or want to explore project-specific information, please use our contact form, email us at info@sovereignhydroseal.com, or call us at +1 646.649.5878, and we can get started.
