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Steel structures are widely used in large-span bridges, offshore platforms, mining equipment and other large-scale buildings. The damage of steel structures will cause significant safety risks in a project. Therefore, it is of great significance to identify and study damage to steel structures. In this study, the propagation of Lamb waves in a steel plate with double cracks is simulated. Using finite element analysis and experimental study, damage identification and damage imaging of double crack damage to a steel plate are performed, and the numerical simulation results are in good agreement with the experimental results. Considering the reflection and transmission of Lamb waves at the welding seam, the location and imaging of crack damage in a welded steel plate are also studied. The imaging results obtained from simulation and experiment show high level in accuracy. By comparing the amplitude of the signal in the propagation process, it is concluded that the transmission energy at the weld seam decreases.
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http://dx.doi.org/10.3390/ma12111800 | DOI Listing |
Nanotechnology
September 2025
China University of Petroleum Beijing, No.18, Fuxue Road, Changping District, Beijing 102249, China, Changping, Beijing, 102249, CHINA.
In fluid catalytic cracking (FCC) processes, vanadium is a primary harmful feedstock contaminant that deactivates catalysts by forming vanadate species which corrode the zeolite framework and damage catalyst structure. Introducing vanadium capture agents is an effective way to enhance the catalytic performance, but the mechanism of the interaction has not yet been fully understood. This study demonstrates that lanthanum-based additives significantly improve vanadium resistance in FCC catalysts.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
September 2025
McKetta Department of Chemical Engineering, The University of Texas at Austin, Austin, TX 78712.
Many soft, tough materials have emerged in recent years, paving the way for advances in wearable electronics, soft robotics, and flexible displays. However, understanding the interfacial fracture behavior of these materials remains a significant challenge, owing to the difficulty of quantifying the respective contributions from viscoelasticity and damage to energy dissipation ahead of cracks. This work aims to address this challenge by labeling a series of polymer networks with fluorogenic mechanophores, subjecting them to T-peel tests at various rates and temperatures, and quantifying their force-induced damage using a confocal microscope.
View Article and Find Full Text PDFRegen Biomater
August 2025
Shi-Changxu Innovation Center for Advanced Materials, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China.
The most significant challenge facing magnesium alloy stents is their ability to withstand complex deformation during their application. To gain a deeper understanding of the impact of stent deformation on the protective capabilities of the coating, this paper presents an amplified stent deformation model. The models were coated with either a low elongation material-Poly(D, L-lactide) (PDLLA) or a high elongation material-Poly(butylene adipate-co-terephthalate) (PBAT), followed by the application of a rapamycin-loaded PLGA as drug-eluting layer.
View Article and Find Full Text PDFData Brief
October 2025
Department of Civil Engineering, University of Science and Technology Beijing, Beijing 100083, China.
The maintenance of metro tunnel support structures is crucial for ensuring the safe and efficient operation of urban rail transit. Under complex stress conditions (including tension, compression, shear, torsion), metro tunnel linings are susceptible to various forms of damage, such as cracking, spalling, segment misalignment, and water leakage. These issues pose substantial challenges to tunnel safety and service life.
View Article and Find Full Text PDFACS Omega
August 2025
Key Laboratory of Safe and Effective Coal Mining, Ministry of Education of China, Anhui University of Science and Technology, Huainan 232001, China.
To investigate the failure behavior and cracking mechanisms in surrounding rock, a true triaxial experimental system and digital imaging were employed to perform compression tests on sandstone specimens containing preexisting flaws. Experimental results revealed the propagation characteristics of microfractures under stress concentration conditions and their correlation with failure patterns. Furthermore, a fracture propagation model was implemented to evaluate the susceptibility of surrounding rock to failure.
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