Carlton Building Parking Garage
Challenge
The second level of the Carlton Building parking garage was constructed half on grade and half above another parking lot. The area where the two halves joined had settled nearly two (2) inches in some places as the soils beneath the on-grade portion were experiencing consolidation, causing the parking slab to settle. Additionally, any repairs needed had to be completed with no disruption to daily operations.
Solution
Approximately 400 pounds of PolyLevel were injected during this job and the two (2) slabs were brought back to a matching elevation. Additionally, the contractor was able to perform this work after regular work hours, thereby eliminating any disruption from daily activity. In order to do this, engineers recommended the use of the PolyLevel 400 series. The PolyLevel 400 series is a two-part expansive polyurethane which expands into a rigid foam that is used to fill voids, stabilize slabs and lift concrete. Once injected under the slab through 5/8th inch “ports,” a chemical reaction solidifies the liquid urethane components into a strong, rapidly setting foam material. In its foam state, PolyLevel is extremely light, weighing two (2) to six (6) pounds per cubic-foot (pcf) compared to other void-filling or lifting materials which can weigh upwards of 120 pcf. That extra weight adds significant pressure to the subgrade, potentially contributing to further settlement. With a typical installed compressive strength of 100 pounds per square-inch (psi), PolyLevel can provide the necessary resistance to support even the heaviest loads.
Project Summary
Product Installed: 400 pounds Polylevel 400; Product Characteristics: 100 psi Typical in Place Compressive Strength, 146 psi Tensile Strength, 69 psi Shear Strength, 19:1 Expansion Rate, 6 pcf Typical in Place Density