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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. 

The trend of offshore wind energy in deeper water that is expected to shift from fixed to floating platforms requires a cost-effective anchor solution for floating offshore wind turbines (FOWTs). Multiline ring anchor (MRA) has been developed as a cost-effective solution for FOWTs due to its capability of anchoring multiple mooring lines, its high efficiency, and its availability to a wide range of soils and loading conditions. While previous preliminary studies on the anchor performance provide useful insights on how the potential advantages of the MRA can improve load capacity, these studies are limited to focusing on optimizing the anchor design in certain soil and loading conditions. By contrast, the MRA will be installed in seabeds under more complex conditions that depend on geological location, water depth of at-place, and environmental conditions, of which wind, current, and wave are major components. These may result in additional substantial extra capital costs, delays in the projects, and safety issues, when the complex conditions are not properly considered. Specifically, the installation time and expenses of the offshore anchor are very susceptible to anchor types, installation methods, and environmental conditions. For this reason, this paper compares two existing offshore anchor installation methods and different anchor types on the basis of their performance under the same severe environmental condition. In evaluating the installability of the MRA, this paper conducts a comparative scenario study. The results show that the anchor installations and anchor handling vessel (AHV) operations