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The behavior of ice particles impacting against a rigid surface is a topic that has gained more and more relevance in the field of transportation safety, particularly in the automotive and aerospace sectors. The present review outlines the various controlled experimental approaches used to study artificial ice particle collisions, describing the setup configurations, particle release mechanisms, and the selection of materials for impact surfaces. It also assesses fundamental studies that measure the coefficient of restitution (CoR or en) and the fragmentation regime of ice upon impact, clarifying how ice particles react when they strike a surface. The review also includes analytical and empirical formulas that describe the critical impact velocity, which determines the different impact outcomes, like bouncing, sticking, or fragmentation and fragmentation distribution of the ice particles. Lastly, it summarizes how particle size, temperature, and material properties affect the impact responses. In addition, the review proposes a visual representation of the different models and how they compare. The visual representation highlights the differences between each model and the transition from elastic to plastic impact responses, and it is instrumental in understanding the conditions under which ice particles leave a residual mass on the impact surface. The insights gained from this review are vital for better understanding the impact of the ice particle phenomenon and mapping the state of the art in this branch of research.

期刊论文 2025-03-01 DOI: 10.1016/j.coldregions.2025.104422 ISSN: 0165-232X

With the rapid development of infrastructure construction on oceanic reefs, calcareous sand, as the primary medium of these reefs, exhibits unique physical and mechanical properties such as high void ratio, low strength, and susceptibility to particle breakage. These characteristics reduce the bearing capacity and stability of pile foundations in calcareous sand foundations. This study investigates the bearing characteristics of high-strength preloaded expansion piles in calcareous sand foundations, taking into account the influence of HSCA high-performance expansion agent dosage through a series of indoor model tests and in-situ tests. The research delves into the load-settlement curves of expansion piles, the distribution of axial force and side resistance of piles, and the effects of Calcareous sand compaction and reinforcement around the piles. The results indicate that adding the HSCA high-performance expansion agent results in compaction preloading of the Calcareous sand around the pile, significantly increasing the expansion stress on the pile side, thereby enhancing the resistance on both the pile side and pile tip. When the expansion agent dosage is 20%, the ultimate bearing capacity can be increased by 56%, and the ultimate side resistance by 63%. The Coulomb strength theory of non-cohesive soil is employed to accurately calibrate the incremental side resistance of the expansion section. A prediction model for the bearing capacity of the expansion pile is established by combining the side resistance prediction model with the ultimate side resistance load-sharing ratio. The research outcomes provide important guidance for the optimization, design, and construction of high-strength preloaded expansion piles in calcareous sand foundations.

期刊论文 2025-01-25 DOI: 10.1038/s41598-025-85412-5 ISSN: 2045-2322

The soil's creep characteristics significantly impact both the effectiveness of the support system and the enduring stability of the engineering structure. During construction, dewatering is often carried out, which results in seepage within highly permeable soils. To scrutinize the creep behavior of silty fine sand under seepage conditions, triaxial compression tests and triaxial creep tests were conducted on the silty fine sand, subject to three distinct seepage flow rates: 0.5 ml/min, 1.0 ml/min, and 1.5 ml/min. The test results indicate that seepage reduces the maximum stress capacity of the soil and increases its creep deformation. Particularly under relatively high deviatoric stress and seepage flow rates, the specimens exhibit three stages: transient creep, stationary creep, and acceleration creep. Notably, the axial creep deformation rate shows a positive correlation with both seepage flow rates and deviatoric stress. Concurrently influenced by seepage and creep, fine particles within the specimen accumulate in the central and upper regions, whereas the lower is characterized by larger particles. The progressive increase in pore water pressure, intricately linked to the impeding effect of fine particles on permeation pathways, catalyzes the creep-induced deformation of the specimen. Based on the experimental results, a modified Burgers model has been established. This model takes into account seepage, sliding damage, and particle fragmentation. A comparative analysis, contrasting the modified Burgers model against calculated values derived from the traditional Burgers and Kelvin-Voigt models, underscores the effectiveness of the proposed model. Specifically, the modified Burgers model adeptly captures the transient creep, stationary creep, and acceleration creep stages of silty fine sand, especially under varying seepage flow rates.

期刊论文 2025-01-01 DOI: 10.1007/s10064-024-04032-x ISSN: 1435-9529
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