98%
921
2 minutes
20
To study the bearing characteristics of rock-socketed single piles on the southeast coast of Fujian Province, we conducted similar material ratio tests and single pile model tests. Initially, based on the mechanical parameters of strongly weathered granite, 10 groups of similar material samples were prepared using iron concentrate powder, barite powder, and quartz sand as aggregates, with rosin and alcohol as the cementing agents and gypsum as the modulating agent. Through triaxial testing and range and variance analysis, it was determined that the binder concentration has the most significant impact on the material properties. Consequently, Specimen 1 was selected as the simulation material. In the model test, the strongly weathered granite stratum was simulated using the ratio of Specimen 1. A horizontal load was applied using a pulley weight system, and the displacement at the top of the pile was measured with a laser displacement meter, resulting in a horizontal load-displacement curve. The results indicated that the pile foundation remained in an elastic state until a displacement of 2.5 mm. Measurements of the horizontal displacement and bending moment of the pile revealed that the model pile behaves as a flexible pile; the bending moment initially increases along the pile length and then decreases, approaching zero at the pile's bottom. The vertical load test analyzed the relationship between vertical load and settlement of the single pile, as well as its variation patterns. This study provides an experimental basis for the design of single pile foundations in weathered granite formations on the southeast coast of Fujian Province and aids in optimizing offshore wind power engineering practices.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC11840283 | PMC |
http://dx.doi.org/10.3390/ma17215324 | DOI Listing |
ACS Omega
August 2025
School of Earth Sciences, East China University of Technology, Nanchang, Jiangxi 330013, China.
The Manglai uranium deposit is located in the Tabei Sag within the Manit Depression, centrally positioned in the eastern Erlian Basin at the core of an ancient valley uranium metallogenic belt. This study analyzed the geochemical properties of 22 clastic and mudstone samples from the Lower Cretaceous Saihan Formation in the Manglai deposit to assess its tectonic setting, provenance direction, redox conditions, and paleoclimatic environment. Key findings reveal that (1) The primary sediment source of the Saihan Formation in the Manglai deposit consists of felsic igneous rocks, situated mainly in a passive continental margin setting.
View Article and Find Full Text PDFJ Environ Radioact
October 2025
Chemistry & Molecular Engineering, Peking University, Beijing, 100871, China.
During the disposal of low- and intermediate-level waste, damage to the fuel casing through oxidation and breakage can lead to the leaching and migration of radionuclides, posing significant risks to the surrounding environment. This study addresses these challenges by highlighting the limitations of relying solely on batch experiments and chemical reaction models, which may lead to overly conservative assessments of radionuclide migration. Instead, a comprehensive approach that integrates both physical nonequilibrium and chemical nonequilibrium adsorption mechanisms is warranted for a more accurate appraisal of the adsorption behavior of Pu within environmental media.
View Article and Find Full Text PDFPLoS One
July 2025
School of Civil and Hydraulic Engineering, Xichang University, Xichang, China.
The Kuanyu ion-adsorption rare earth element (REE) deposit, Sichuan's first economically viable resource of its type, remains underexplored in terms of REE fractionation and enrichment mechanisms within its weathering profiles. This study systematically resolves REE speciation patterns and light-to-heavy REE (LREE/HREE) differentiation processes, advancing the metallogenic framework fo r such deposits. Analytical results demonstrate: (1) A vertically progressive enrichment of LREE-dominated REE concentrations from bedrock to topsoil, with the fully weathered layer serving as the primary enrichment zone; (2) Weathering of primary REE-bearing minerals and subsequent secondary mineral formation as drivers of elemental redistribution; (3) Contrasting controls by clay minerals, iron-manganese oxides, and humic acids-clay minerals preferentially adsorb LREEs, while iron-manganese oxides exhibit stronger HREE affinity through inner-sphere complexation, and humic acids enhance HREE mobility via stable complex formation.
View Article and Find Full Text PDFToxics
June 2025
Langfang Natural Resources Comprehensive Survey Center, China Geological Survey, Langfang 065000, China.
This study investigates the weathering crust composite of serpentine, pyroxenite and granite in the Niangniangmiao area, the weathering crusts inside and outside the mining area were compared respectively, systematically revealing the distribution patterns, migration pathways, and ecological element activity characteristics of high-background elements (e.g., chromium (Cr) and nickel (Ni)) through precise sampling, the Tessier five-step sequential extraction method, and a migration coefficient model.
View Article and Find Full Text PDFFront Public Health
July 2025
Faculty of Environmental Sciences and Natural Resource Management, Norwegian University of Life Sciences, Ås, Norway.
Introduction: Exposure to radon-222 (Rn) is a common problem in areas with high uranium-238 (U) content in the subsurface. The gas may enter dwellings through cracks and gaps in the foundation, or groundwater collected for household use. It is well documented that Rn poses a health risk, especially in high concentrations.
View Article and Find Full Text PDF