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Effective slope stabilization measure in deep open-pit mines not only ensures the safety of employees and equipment, but also makes sound economic sense. Based on field investigations of a landslide at the Lishan Iron Mine, south China, an innovative and effective method for slope remediation is proposed. An in situ foundation embankment was first created by excavating an anti-slip foundation trench, then the slope was stabilized by building a restraining embankment against the slope. The in situ foundation embankment had a dense structure which provided good resistance both to slip and to overturn. The restraining embankment was constructed out of mining waste rock and reduced the potential for slope failure by diminishing the potential free area of the slope and inhibiting the development of fractures in the rock mass forming the slope. In view of the structural characteristics of the in situ foundation embankment, an analytical solution for the safety factor of the embankment slope is deduced using theoretical analysis and numerical simulation for various combinations of geometric parameters. The results show that the safety factor of the embankment decreases with an increase of step height and step slope angle and increases with an increase of platform width and that step slope angle is the key parameter which affects the safety factor and both the maximum displacement and maximum plastic strain. The reliability of the proposed method is validated using field monitoring results from the Lishan Iron Mine after the embankment construction. This mine has now been safely running without landslides for two hydrological years after the stabilization works were constructed. [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]

Developing an accurate and efficient forward model of the dynamic response of pavement structure is of great significance for obtaining the design parameters of the layered pavement structure through an inverse calculation based on the measured pavement data. However, the existing algorithms rarely consider the interlayer contact. Based on the traditional spectral element method (SEM), this study proposes a new forward model to simulate the falling weight deflectometer (FWD) dynamic tests for the transversely isotropic layered pavement structure. The interfaces between the pavement layers can be imperfect, and the displacement boundary conditions are discontinuous. Moreover, the developed model considerably enhances the efficiency of the model in solving the dynamic response of transversely isotropic layered media by avoiding the infinite integration in integral transformation. Numerical examples verify the accuracy and efficiency of the model developed in this study. At the same time, an extensive parameter analysis is conducted on the interlayer contact of the pavement structure and inhomogeneity of the layered soil, which provides a reliable, numerical, theoretical basis for the design of pavement structure. [ABSTRACT FROM AUTHOR]

Cone penetration test (CPT) has been commonly applied as a site investigation tool and a laboratory measurement method in centrifuge tests to study soil properties. In this research, large deformation finite element (LDFE) analysis is utilized to realize the simulation of continuous cone penetration in two-layered clay deposits in centrifuge testing, with the aim of better interpreting the shear strength of cone penetration testing data. The numerical model is validated against previous published data, where good agreement is obtained. From LDFE results, it is concluded that for stiff-over-soft clay, the measured peak resistance in top layer is underestimated and the resistance curve in bottom layer is overestimated at the transitional depth where the stiff soil is trapped below the conical surface of cone. However, for soft-over-stiff clay, owing to the insufficient thickness for cone to reach its full resistance, the effect of top layer thickness needs to be considered. Finally, based on intensive numerical modeling results empirical formulae are proposed to quantify the prediction errors and to obtain a more accurate prediction for the soil profile using CPT data in centrifuge tests. [ABSTRACT FROM AUTHOR]