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[Introduction] The increasing traffic and the increasingly tight construction cause the roads to be widened and rebuilt. In order to further study the stability of the embankment, the change of the mechanical characteristics of the pile under the original embankment is analyzed when the soft foundation embankment is widened. [Method] After verifying the centrifuge model,a three-dimensional numerical model of the widened embankment and the original embankment was established using Abaqus. Based on the comparative analysis, the influence of gravity, deformation modulus, strength parameters of widened embankment on the mechanical characteristics, deformation behavior and failure mode were carried out. [Result] The numerical simulation results show that the piles under the embankment had different contributions to anti-sliding. The piles close to the slope are mainly subjected to bending and shearing, and the piles far away from the slope are mainly affected by the axial force. The weight of the widened embankment affects the mechanical characteristics of the pile in the original embankment: the main performance is that the bending moment and shearing for piles in the original embankment reduced, and the axial force increased; the displacement of piles in the original embankment increased, in which the vertical displacement increment near the original slope foot is the largest and the largest lateral one is located in the middle of the original embankment. The soil weight of the widened embankment significantly affects the vertical displacement of the original embankment, but its deformation modulus and strength parameters almost have no obvious effect. After the embankment is widened, the mechanical characteristics of the pile in the original embankment change under the load. The potential failure mode is changed from bending-shear zone, bending zone and compression zone to bending zone and compression zone. [Conclusion] The model can verify the centrifuge test results, and the results can provide guidance for the stability analysis of embankment widening.

In order to study shaft wall damage resulting from ore drawing in ore passes, a theoretical model for predicting the shaft wall damage to high-depth inclined ore passes is constructed based on field surveys of 25 ore passes in a deep mine in Yunnan, China. The mathematical expression of the total shaft wall damage volume is derived using the contact mechanics theory. Considering the structural characteristics of ore passes, and taking No. 1, 2, 3, and 9 ore passes as examples, combined with numerical simulation and an engineering case, the rationality of the proposed theoretical model is verified with respect to the initial collision position and the damage conditions of the shaft wall. The influence of, and sensitivity to, the ore block size P and the structural parameters of high-depth inclined ore passes on the total shaft wall damage volume Qtol are quantitatively analyzed. The results show that the calculation results of the theoretical model and numerical simulation are in good agreement with the actual engineering situations. Moreover, the ore-pass dip angle θ and the inclined angle of the chute α have a significant impact on the damage to the shaft wall, while the effects of the ore-pass depth H and the shaft diameter D are comparatively minor. With an increase in θ or α, Qtol generally first increases and then decreases. Qtol increases exponentially with P and increases steadily with D. H affects Qtol by influencing the collision frequency between the ore and the shaft wall. Therefore, in the mining design of deep mines, θ and α should be minimized as much as possible or adjusted to approach 90°, thereby reducing damage to the shaft wall. Secondly, ore block size should be strictly controlled to prevent collapses in the shaft wall caused by large ore blocks. This work provides technical support for the long-term safe operation of high-depth inclined ore passes. [ABSTRACT FROM AUTHOR]

Stimuli‐responsive structural‐color materials have received widespread attention in information encryption due to the significant color changes under different stimuli. However, the trade‐off between the capacity of information input, security level, cost, and large‐area manufacturing greatly limits the application of structural colors in encryption. Herein, dynamic high‐capacity and high‐resolution encryption are achieved by implementing printed total internal reflection (TIR) structural color and computer‐aided image recognition. The printed TIR microstructures are prepared with relative humidity (RH) responsive polymer, which form a heterogeneous wettability system, and can exhibit vibrant color variation with humidity. As the implemented RH is changed, the printed microstructures will expand or shrink precisely, enabling a full‐color modulation across the visible light range. With the color change, each structural‐color pixel can be specifically encoded, allowing for this to encrypt dynamic information within the same pattern at different RHs. Furthermore, This study can precisely integrates tremendous different pixels and easily prepare various encrypted patterns, which guarantee the high‐capacity information input in a low‐cost way. Moreover, through computer programming and algorithm reading, the structural‐color patterns can be decoded and decrypted in real‐time, thus offering great potential for further encryption, anti‐counterfeiting, multiplexing encoding, and data storage. [ABSTRACT FROM AUTHOR]

SignificanceAdjusting the floating states when objects float on water shows great potential for assembly, mineral flotation, nanostructured construction, and floating robot design, but the real-time regulation of floating states is challenging. Inspired by the different floating states of a falling fruit, we propose a facile strategy to transform the object between different floating states based on a three-segment three-phase contact line evolution. In addition, the potential of floating state transformation in solar-powered water evaporation, interface catalysis, and drug delivery is demonstrated. These findings provide insights into floating regulation and show great potential for floating-related applications.