A large tunneling contractor found itself in a difficult situation with a large flowing water leak in a new rock tunnel 20 metres underground. During tunnel construction, localized areas of bad ground conditions were encountered, characterized by heavily fractured rock.
Conventional cement grouting was used by the tunneling contractor to control water inflows in some of these areas. An evaluation of the particular site conditions by the Multiurethanes crew determined that debris and broken ground made it impossible to accurately identify the primary water-bearing fracture as experienced by the tunneling crew when initial injections were washed out by the large water inflow.
An innovative solution involving chemical grouting through single grout hole injection while isolating and identifying nearby localized leaks was successfully implemented. The specialized nature of the water cut-off grouting work required a combination of materials, equipment and experience, including Multiurethanes Universal Resin, a pneumatic chemical pump and skilled grouting techniques performed by our experienced grouting specialists.
The secret to this successful water cut-off project was the application of appropriate grouting techniques, equipment and materials for the existing site conditions.
Due to the high water table present in the region, an underground water main chamber encountered an unavoidable inflow of water through the precast segment joints.
Working within the chamber, a series of parallel holes were drilled directly into the joints voids at a depth of 4 inches between the precast segments. Packers were installed into the drilled holes and flushed with Water/Acid solution to rid debris from holes and the voids. Chemical grout was then injected into the joints, filling the void and creating a semi-rigid foam barrier.
Chemical grout injection using Multiurethanes Universal Resin, Universal Accelerator, 3/8″ plastic packers and two chemical grout pumps were used to seal the joints between the precast chamber segments. The technique eliminated the water leakage, allowing for the chamber to be returned to service.
Multiurethanes provided soil stabilization for a complex tunnel project with several site restrictions including no drilling from surface and working in close proximity to sewer and water mains. Our solution involved sodium silicate grouting delivered through horizontal injection pipes arrayed out from inside a shaft. Injection of Universal Resin was also performed in localized areas. We specialize in projects with technical, complex grouting requirements.
Our technical team developed a solution to lift train track crossings on wood ties by pressure grouting under the tracks. This new approach was fast, reliable and surprised the utility contractor, who had been looking for this solution for a long time. Multiurethanes technicians bring practical product knowledge and hands-on experience for applying proven grouting techniques to new applications.
Performed microfine cement grouting and water-stop operations using polyurethane resins, and provided soil stabilization in cross passage tunnels along the road in a light rail transit (LRT) line construction project.
Location: Fort McMurray, AB Sector: Energy Category: Water Cut-off
A general contractor required Multiurethanes’ assistance with the installation of Hydrotite CJ-3030 in precast concrete panels in the construction of a headwall, as part of the overflow system at an oil sands facility, north of Fort McMurray, AB.
Unlike a conventional, poured in place concrete headwall with engineered waterstop, this installation presented various challenges. This application required the Hydrotite to be installed within tight tolerances to allow the precast panels to line-up correctly. Additionally, in order for the Hydrotite to be effective, it had to firmly adhere to the precast concrete surface.
A team of six members from the general contractor’s personnel was trained by Multiurethanes’ engineers on how to install Hydrotite on the precast headwall panels. Following specific guidelines, the training provided for the client detailed the proper surface preparation, the appropriate positioning and the anchoring method for this Hydrotite installation.
Multiurethanes’ on-site technical support continued throughout all stages of the Hydrotite installation. After the completion of the Hydrotite application, the panels were successfully placed on a concrete leveling pad to form the required headwall.