Slurry Application Rate Calculator
This slurry application rate calculator is designed primarily for pavement applications in which the soil or aggregate will be treated in place on the job site. The calculations assume that the slurry is comprised of portland cement and water. This calculator is provided as a convenient tool for use by qualified personnel who are able to develop appropriate inputs based on accepted practices and evaluate the outputs with skill and judgment.
Regarding the inputs, typical values for cement concentration range from 2 to 8 percent by dry weight of soil or aggregate, depending on the soil or aggregate type and the treatment objectives. The cement-treated layer thickness usually ranges from 6 to 12 inches, with the maximum value being limited by the thickness that can be adequately mixed and compacted in a single lift. The dry density of the cement-treated layer in pounds per cubic foot is determined by multiplying the maximum dry density determined from laboratory compaction testing of the soil or aggregate treated at the specified cement concentration by the required minimum percent compaction, which is commonly specified to be around 95 percent. The water-cement ratio of the slurry is typically specified to be in the range of 0.40 to 0.45, and the air content, which can be determined from testing of the slurry, is often in the range of 2 to 4 percent by volume. The volume of slurry per truck load is frequently specified to be less than the full capacity of the truck to avoid spillage during transit.
Regarding the outputs, the cement and water weights in pounds per cubic yard of slurry effectively constitute the slurry mixture design. The slurry application rate is the weight of slurry in pounds that should be placed per square yard to achieve the specified cement concentration. Finally, the treatment area per truck load is the area in square yards that should be treated with the slurry in each truck carrying the specified slurry volume.