To investigate the effect of dimensional changes on the mechanical properties of cemented tailings backfill (CTB), uniaxial compression tests are performed on square CTBs of four different sizes. Combining digital image correlation (DIC) and acoustic emission (AE) methods, the fracture process and AE behavior characteristics of backfills with different sizes are analyzed. The results show that as the backfill size increases, its uniaxial compressive strength decreases, and its strength stabilizes gradually when it measures 100 mm. Under uniaxial compression loading, surface cracks on the smaller specimens evolve rapidly and aggressively, with no significant shedding area, whereas the larger specimens show plastic failure. The cracks expand and penetrate gradually, forming a large shedding area. As the specimen size increases, the backwards trend of the peak value of the ringing count relative to the peak value of the stress becomes increasingly evident. Combining the change law between the value and the average frequency centroid, the sudden drop point of value and the lowest value of average frequency centroid can be regarded as the precursor of macroscopic damage.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9699267 | PMC |
http://dx.doi.org/10.3390/ma15228038 | DOI Listing |
Polymers (Basel)
January 2025
Faculty of Physics, Lomonosov Moscow State University, Moscow 119991, Russia.
A finite element model of the local mechanical response of a filled polymer composite to uniaxial compression is presented. The interfacial layer between filler particles and polymer matrix is explicitly modeled as a third phase of the composite. Unit cells containing one or several anisometric filler particles surrounded by interface shells are considered.
View Article and Find Full Text PDFPolymers (Basel)
December 2024
Science and Technology on Reliability Physics and Application of Electronic Component Laboratory, China Electronic Product Reliability and Environmental Testing Research Institute, Guangzhou 511370, China.
During the thermal aging process of epoxy resin, microcracks, interfacial delamination, and warpage are the key factors leading to semiconductor device damage. Here, epoxy-resin specimens (EP-Ss) and epoxy-resin/silicon-wafer composites (EP-SWs) were prepared to analyze the distribution of residual stress (RS) in epoxy resin and its thermal aging process changes. The uniaxial tensile approach and Raman spectroscopy (RAS) showed that the peak shift of aliphatic C-O in EP-Ss was negatively correlated with the external stress, and that the stress correlation coefficient was -2.
View Article and Find Full Text PDFSci Rep
January 2025
Department of Geology, College of Applied and Natural Sciences, Addis Ababa Science and Technology University, Addis Ababa, Ethiopia.
Coal is a critical energy resource for global industries, and its extraction from open-pit mines requires effective slope stability management to ensure safe and efficient operations. This study evaluates the slope stability of the Tolay open-pit coal mine in Ethiopia, located in the Jimma zone, where geological conditions, including basalt, mudstone, and weathered soil layers, influence slope behaviour. The primary objective was to assess slope stability and recommend optimization strategies for safer mining.
View Article and Find Full Text PDFCells
December 2024
AO Research Institute Davos, Clavadelerstrasse 8, 7270 Davos, Switzerland.
In the context of bone fractures, the influence of the mechanical environment on the healing outcome is widely accepted, while its influence at the cellular level is still poorly understood. This study explores the influence of mechanical load on naïve mesenchymal stem cell (MSC) differentiation, focusing on hypertrophic chondrocyte differentiation. Unlike primary bone healing, which involves the direct differentiation of MSCs into bone-forming cells, endochondral ossification uses an intermediate cartilage template that remodels into bone.
View Article and Find Full Text PDFSci Rep
January 2025
LECIV - Civil Engineering Laboratory, UENF - State University of the North in Rio de Janeiro, Av. Alberto Lamego, 2000, Campos dos Goytacazes, Rio de Janeiro, 28013-602, RJ, Brazil.
The correct choice of a stone aggregate for railway ballast is directly related to the stability, safety, efficiency, and maintenance costs of the track. The aggregate must meet several criteria to ensure it is the most appropriate material. Thus, the present study aimed to evaluate four distinct stones: two granites, a diabase, and a basalt, all mined in the eastern region of the state of São Paulo, Brazil, regarding their applicability as ballast.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!