Project at a Glance
Material Density: 30 pcf, 45 pcf, and 60 pcf
Base Slurry Mix Design: .60 water cement ratio
A customer of Richway’s was approached about installing cellular concrete into a containment vessel containing a lot of waste and debris. It was critical to have everything be fully encapsulated. Although there are standardized tests for measuring/gauging slurry flowability, it was decided by the customer to run some of their own tests. The objective was to be able to observe the flowability of cellular concrete at varying densities. So they could feel confident that complete encapsulation would in fact occur.
Using forms constructed of plywood measuring 1’ deep X 1’ wide X 12’ long, two boxes for each density of 30PCF, 45PCF, and 60PCF were filled from one end. As seen in the photos, a number of PVC cylinders were placed in the middle of three of the box forms, to further replicate debris that the cellular concrete would need to flow in and around.
The base slurry mix design was simply a neat cement slurry with a .60 water to cement ratio and we used our CF-CT30D to produce cellular concrete. And, as expected, the 60PCF material did indeed flow the best. While there are a vast number of factors that can be changed to enhance flow characteristics for any given density or mix design, keeping the scope of the testing, and variables, limited made best sense for this phase of testing.
One thing to bear in mind is that this test applied very little to no head pressure upon the material once it was in the box form. If the box were enclosed with an injection port on one end and a vent on the other, it would be expected that any of the given densities would have completely filled the box with very little pressure. Or had the box form been much deeper, say three feet deep, it would be expected that any of the densities tested would have flowed to the far end of the form, given the increased head pressure. A unique characteristic of cellular concrete is its ability to be pumped great distances, thousands of feet is not uncommon. The viscosity and density of the material contribute to this feat and make cellular concrete a great choice for void filling applications.