The goal of the project was to explore the use of x-ray micro computed tomography (µCT) to investigate the effects of deicing salts on soils and soil-compost mixtures that are typically used as stormwater filter media (SFM). Identical samples were moistened and compacted into small polycarbonate tubes. The samples were prepared carefully controlling the particle size distribution and the dry density achieved by compaction. The samples were dried until they reached a steady minimum mass. To obtain the pre-flow internal structure of samples, they were scanned with a Bruker’s SkyScan 1173 µCT system. Flow tests were conducted on samples at three different gradients, with or without NaCl in influent water, and with or without compost in the samples. Most of the tests were conducted on triplicate samples. During the flow tests, the flow rate was measured at reasonable intervals. After running the flow tests, until an asymptotic flow rate was reached, the samples were again dried and scanned with the same µCT system, to get the post-flow internal structure of samples. Overall, 24 samples were scanned pre-flow and post-flow, with an aim to study the effects of experimental variables (NaCl, compost, hydraulic gradient), by analyzing the sets of µCT images. The image-sets have so far been analyzed with (1) Bruker’s CT-Analyser Version 1.13 software, and (2) Avizo Fire 8 software. We are currently working on using the Avizo results (3D individual objects) in coupled DEM-CFD (discrete element method and computational fluid dynamics) simulations.
|Work Title||Pre-flow images|
|License||CC BY-NC-ND 4.0 (Attribution-NonCommercial-NoDerivatives)|
|Deposited||October 03, 2017|