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This paper offers a comparative study of two soils- Glauconite and Ottawa F65- utilizing X-ray micro-computed tomography (µCT) scan. The tendency of glauconite sand to transform from coarse to fine-grained material through particle crushing poses challenges in terms of stability and strength, particularly in foundation engineering and offshore site investigation. This paper investigates the particle size distribution and explores the subtleties of particle characteristics. Non-invasive µCT and 3D image analysis are used to measure and compare particle shape parameters: median aspect ratio (0.56 for Glauconite,0.54 for Ottawa F65), median convexity is 0.86 for both soils, and median sphericity (0.81 for Glauconite, 0.83 for Ottawa F65). By drawing comparisons between the statistical data of particle shape parameters from both soils, insights are gained into their morphological characteristics. Additionally, fitted Johnson distributions are provided for 3D Aspect ratio, sphericity, and convexity which may be useful for discrete element method modeling of these soils. 

This paper presents a study on the impact of rigid awns and their deployment on interface friction. Awns are appendages attached to the exterior surface of a geo-system and bio inspired by grass seeds. Awns provide frictional anisotropy and assist the seed in self-embedding into the soil or clinging to animal hair. In geo-systems, like piles, deployable awns can provide frictional anisotropy reducing installation effort and increasing global capacity. In addition, flexible awns can be folded up to enable space saving for transportation. This paper presents the results from a set of interface shear tests in a modified direct shear device. Single rigid awns were tested at various angles, from horizontal, as a pseudo-static simulation of deployment, in loose and dense sand, in both the cranial (towards the head) and caudal (towards the tail direction). It is shown that awns opened at larger angles provide higher interface friction and that shearing in the cranial direction provided more resistance than in the caudal direction. This demonstrates that deployable awns could be used in geosystems to provide friction anisotropy and increase capacity.