Polyurethane is the process of injecting expanding polyurethane grout into voided areas, inside structures or under slabs-on-grade in order to fill voids or relevel slabs. Polyurethane grouting is a fast, efficient repair process for improving settled and unstable concrete. From sidewalks to interstates, and everything in between.
There are several times when polyurethane grouting is the only restoration process that will address a problem. Here are some of the times when polyurethane grouting is essential:
Because of its high development force and ability to spread under large areas of slabs and structures before expanding, high-density polyurethane can lift extremely heavy slabs with ease. These involve roadway slabs, bridge approaches, rail crossings and slabs with heavy loads, such as machinery bases and floors with backup battery power packs.
Due to the small, infrequent holes, dustless drilling is easy. Additionally, because there is a mechanical connection between the injection equipment and the slab, no material is exposed to the surface or surroundings. Automated, mechanical devices on the injection equipment prevent leakage of material when not injecting. We use special dustless drilling equipment for most interior jobs.
Polyurethane grouting accepts small (dime-size) holes that can be stored infrequently. It is a perfect repair method for settled slabs which have decorative coatings, surface treatments or other characteristics, such as brick and stone overlays. Injection holes can be patched with stained concrete to blend in with floor coverings. For repairing slab floors with wood, we use a 1″ whole saw to cut a small access area to the floor, which can then be puttied back into place after lifting is completed. For carpeted areas, three sides of 2″ squares can be cut to reveal floor and then be glued back down after injection.
The usual cause of slab settlement is inadequate compaction or bearing capacity of the underlying soils. Because high-density polyurethane is lightweight (typically 2.5 to 6 pounds per cubic foot), there is very small added weight transferred to the underlying soil as part of repairs. This helps to minimize the chances of resettlement. Sand-based and cementitious grouts applied for slab jacking or pressure grouting typically weigh more than 100 pounds per cubic foot. The weight savings with polyurethane grouting are significant.
Because high-density polyurethane is stored and transported as a liquid which then expands. A single non-CDL box truck can easily carry more than 80 cubic yards of expanded material. The equivalent for slab jacking grout would need more than 6 large dump truck loads and onsite handling equipment. Raw polyurethane material is carried in standard chemical totes. So is easily transported, stored and handled on job sites.
Have questions about an application for polyurethane grouting Alameda County? Email us at email@example.com, or call (650) 241-2400 for more detailed information on our services.