Stabilize and Strengthen Soils
Our cementitious grouts are ideal (economical, effective, enduring, and non-hazardous) for improving the soil character and function of many geotechnical challenges. Once injected into the soil, the grout works for centuries...stabilizing weak soil structure, imparting load-bearing compressive strength, and sealing against leachate within almost any soil type—even the fine-grained soils that defeat effective penetration by other grouts.
If a potential building site is found to have existing soil conditions that do not support the project in terms of soil stability, load-bearing capacity, compaction requirements—or any of the other concerns brought on by poor native soil or underlying structure—the site need not be rejected outright. The right soil-permeating cementitious grout can cost-effectively bring the soil into alignment with the required geotechnical needs. Even sites that were built up using indiscriminate infill methods, soil types, and junk fills can often be stabilized and brought up to specification with a high-performance grout. Successful rehabilitation of those “brownfield” sites scores points in the LEED certification ledger as well.
Each year, at a Geotechnical Grouting Conference held at the Colorado School of Mines in Golden, Colorado, sand column tests are used to demonstrate the permeation ability of different grouts. The 2013 tests included a newly formulated cementitious grout designed with the flexibility to permeate various soil types—US Grout Ultrafine VX. This grout features the same impressive average particle size of 3 micros, but utilizes an adaptable liquid superplasticizer as an accelerant and dispersant.
Using a standard 2 to 1 water/grout ratio, and injected into a very fine colloidal silica sand, US Grout Ultrafine VX charged up the 60-inch sand-filed column in an unheard-of 80 seconds. The PSI at the pump was only at an eight when the grout hit the top (test allows for up to 10 psi and time allowance is 20 minutes). No other cement grout came close…not even when adjusted to a more favorable grout/water ratio.
The importance of such impressive permeation performance by a cementitious grout is welcome news in the grouting industry. Now, with US Grout Ultrafine VX, expensive, often short-lived chemical grouts have an adaptive cementitious brother that can effectively handle the toughest jobs.
The key to effective soils permeation is this: particle size and rheology. Not viscosity. Particle size and rheology determine a grout’s ability to penetrate and properly disperse in soil.
The erroneous practice of tweaking the viscosity of a standard cementitious grout to amp injectability doesn’t work. It results in lower compressive strength and water bleed-off during crystallization, riving the grout seal with porous, interconnected wormholes and resulting in an undesirable density matrix. As referenced above, the remarkable success of US Grout Ultrafine VX in the sand column tests at the Geotechnical Grouting Conference is a direct result of the ultrafine particle size and the rheological properties designed into the grout formulation.
Not only do our cementitious grouts attain impressive soil permeation rates, they can do so even when using a reduced water-to-cement ratio that can achieve a compressive strength of over 8000 psi.
US Grout products are the only pumice-pozzolan charged cementitious grout on the market. The pumice provides a second, complimentary reaction—a pozzolanic reaction—that adds an incredible performance boost to the standard water-cement hydraulic reaction that forms the binding concrete paste. Good things happen as the result of the pozzolanic reaction: the lifespan, strength, and the effective performance of the grout increases because the pumice (via the pozzolanic reaction it ignites) works to consume and convert the deleterious byproduct compounds that are produced by the cement/water hydration reaction, effectively densifying and tightly welding the cured grout matrix. This virtually impermeable grout can then resist the problems that plague ordinary cementitious grouts: no expansive cracking and failure from within, ultra-resistant to penetrating attacks from water and chemicals without.
The rheological properties of a grout are an important aspect of a grout mix design: properties like bleed, segregation, water/cement ratios, particle size and distribution of the cementitious materials. Higher strength grouts typically have low permeabilities and thereby resists chemical attacks and physical degradation. When the rheology is right for the soil structure, and, boosted by the grout-densifying pozzolanic reaction ignited by the pumice pozzolan, a US Grout product can effectively function for thousands of years.†
† longevity projections from research referenced on pages 23, 26, and 78 of AECL’s Whiteshell Laboratories research findings and analysis on the ultrafine cementitious grout developed by the DOE’s Sandia National Laboratories. Also inferred from the practical proof of pozzolanic-charged Roman concrete.
Ask a geotechnical engineer to list the capabilities, performance results, and usage parameters of an ideal grout, and you would likely hear the following: wide range of water-to-cement ratio possibilities, little to no bleed, a generous injectability window, adjustable rheology and set time, impressive strength, volume stability, extremely low hydraulic conductivity, negligible contraction cracking from heat of hydration, self-healing ability, resistance to chemical attack. And then these things too: a ready-to-mix-and-pump product, custom blend options, a stable and competitively-priced supply, rigorous quality controls that insure consistent performance, expert and experienced technical support, an international distribution network, and a safe-to-use, non-hazardous product. US Grout Ultrafine and Microfine grouts deliver all of that.
Designed for job-specific flexibility, US Grout type VX, paired with our USG-Super (a super p), can work its effective magic in a wide range of soil permeation and stabilization projects. And to help project engineers quickly dial into the grout-plasticizer-soil standard for each project, US Grout provides a testing service that utilizes project-specific soil samples. The returned starting point means less guesswork and quicker completion times.
|TYPICAL APPLICATIONS FOR CEMENTITIOUS GROUTS
SOIL STABILIZATION, GROUNDWATER CONTROL, SOIL STRENGTHENING APPLICATIONS
|LARGE-SCALE CIVIL PROJECTS|
Cementitious grouts are used for a wide variety of civil-scale construction projects. To stabilize soil or control groundwater, these substantial constructs require a significant amount of grout, and cost efficiencies mean cementitious grouts are typically the first consideration.
|COMMERCIAL CONSTRUCTION PROJECTS|
No matter the size of a construction project, the cost of buying both in-soil performance and performance longevity matters. US Grout Microfine and Ultrafine cementitious grouts are economical, permanent, environmentally low-impact, safe to use, and geologically effective in a wide range of soil types.
Cementitious Grouts are also used extensively to help stabilize and extend the life of deteriorating infrastructure.
Rest easy. US Grout products were formulated for tough grouting situations, but designed to be placed by conventional grout practices and equipment. Our grouts offer a generous two-plus hour injectability window, are simple to properly mix, and are safe to use.
US Grout products are sourced and made in America, are available via an international distribution network, and backed by many years of practical grouting experience.
As the world-wide distributor for US Grout products, Avanti International (www.avantigrout.com • 800-877-2570) provides the customer service, objective professional advice, material estimates, and the caliber of world-class technical support that comes only from 35 years of geotechnical experience.