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Many building structures in the southwest of China are constructed on slopes due to its mountainous terrain characteristics. Therefore, it is crucial to accurately study the stability of slopes and building structures during the construction and operation stages. Traditional numerical simulation methods for slope stability often analyze from the perspectives of stress and strain. However, due to the complex changes in stress and strain inside the slope, the traditional methods are not only complex but also result in some errors. The slope failure is essentially a procedure of energy transformation, dissipation, and mutation. Therefore, the slope stability can be analyzed more effectively from the perspective of energy changes. In this paper, an energy field visualization procedure is developed and applied to analyze the failure mechanism of slopes. First, the energy calculation principle of slopes was derived based on the principle of thermodynamics. Then, FLAC3D7.0 was used to develop the energy visualization procedure for slope. It was applied to a classical two-dimensional slope to calculate the safety factor of slopes and then compared with the traditional methods. Finally, the procedure was applied to two practical slopes and building structure engineering cases to study their stability and provide suggestions for practical construction. The research results show that the energy visualization procedure can correctly simulate the energy evolution principle in the procedure of slope failure. The sudden change of energy can be used to determine the safety factor and sliding surface of slopes. The error of the slope safety factor calculated by this procedure is only 0.02, indicating that the procedure is correct. The deformation and failure of slopes are essentially driven by energy. There are corresponding relationships between the energy stability stage and the slope equilibrium stage, the energy dissipation stage and the slope deformation stage, and the energy mutation stage and the slope failure stage. The preferred backfill scheme of high-fill slope engineering is one with less variation in gravitational potential energy and a greater increase in elastic strain energy. Pile foundation and building structure are effective methods to increase slope stability. Therefore, the energy visualization procedure developed in this paper can more intuitively and accurately analyze the stability of slopes and building structures. [ABSTRACT FROM AUTHOR]

The adverse effects of the frequent reservoir earthquakes (REs) and the severe degradation of the hydrofluctuation belt (HFB) on the long-term stability of bedding bank slope since the Three Gorges Reservoir Area (TGRA) impoundment were considered fully in this paper. Under such complex conditions, the dynamic response pattern and instability mechanism of typical bank slopes were investigated systematically by using a method of combining field survey, laboratory shaking table (ST) model test, and Universal Distinct Element Code (UDEC) numerical exploration. The research shows that the degradation forms of the HFB of typical bank slopes in the key field survey of the TGRA can be arranged into four types: erosion (denudation), corrosion (suffosion), avalanche (collapse), and slip (flow). The dynamic response of slope shows obvious characteristics of "surface effect" and "elevation effect," and the cumulative displacement (CD), damping ratio (DR) and natural frequency (NF) of slopes show a trend of gradually increasing, and increasing and decreasing, respectively. Meanwhile, the "S–type" cubic function and "Steep rise type" exponential function can be used to characterize the cumulative damage degree (CDG) of slope at the excitation stages of microseisms—small seisms and strong seisms, respectively. Subsequently, the dynamic evolvement process for cumulative damage and unstable failure of slope considering the impact of degradation of rock mass in the HFB was obtained, and there are good agreement between the model test and numerical exploration results. Furthermore, fully considering the influence of slope height (SH), slope angle (SA), thickness of bedding plane (TBP), dip angle of bedding plane (DABP), dynamic load amplitude (DLA), dynamic load frequency (DLF), height of water level of the HFB (HWHB), degradation range of the HFB (DRHB), and degradation shape of the HFB (DSHB), the CD of slope subjected to continuous excitation of multiple seismic loads increases in the form of exponential function, the dynamic stability coefficient (DSC) of slope decreases slowly first and then drops sharply, and the response degree of slope deformation and sliding velocity is obviously different. Especially, the sensitivity level of every preceding factor to the dynamic stability of slope based on the orthogonal analysis method (OAM) is in the order of DLA > DRHB > SA > SH > DLF > HWHB > DSHB > DABP > TBP. [ABSTRACT FROM AUTHOR]

High‐entropy alloys (HEAs) are gradually replacing armor‐piercing core materials such as depleted uranium and tungsten alloys in high strain rate, high temperature, and high pressure service environments due to their excellent mechanical properties (high strength, high strain rate strengthening effect, and strong shear self‐sharpening characteristics). The dynamic compression performance of TiZrHf‐based HEAs with different elements, different strain rates, and multiple loadings is tested by the self‐constructed separate Hopkinson compression bar experimental system. The results show that the TiZrHfCu0.3 alloy has the largest elastic modulus and the strongest deformation resistance. TiZrHfAl0.3 and TiZrHfCu0.3 show a certain strain rate effect. The elastic modulus increases with the increase of loading times. The ultimate strength of TiZrHfAl0.3 remains unchanged after multiple loading, while the ultimate strength of TiZrHfCu0.3 and TiZrHfNi0.3 decreases gradually. [ABSTRACT FROM AUTHOR]

To solve the problem of vehicle bump at bridge head in soft soil subgrade, a no-excavation treatment technology for composite foundation using jet grouting pile with variable stiffness was proposed. First, the influences and the sensitivities of the pile length, the pile diameter, the pile spacing, the number of pile rows, and the grouting depth on the treatment effects were analyzed by two-dimensional numerical simulation method. Then, a treatment scheme was proposed. Finally, the three-dimensional numerical simulation method was used to analyze and verify the scheme. The results show that the longer the pile length, the larger the pile diameter, the larger the pile spacing and the more the pile rows, the better the settlement control effect. However, with the increase of the grouting depth, fee settlement control effect first improves and then remains unchanged. And there are optimal values of fee pile diameter, the pile spacing, the number of pile rows and the grouting depth, which are 0.8 m, 2.0 m, 2, and 5 m to 8 m, respectively. The sensitivity of the pile length is 1.02, much higher than feat of other parameters. Thus, it is suggested to change the pile length to realize variable stiffness. After treatment, the consolidation settlement is controlled within the inner subgrade. And the settlement from the bridge head to the road extension direction shows a good gradual change effect, alleviating vehicle bump at bridge head. [ABSTRACT FROM AUTHOR]

Due to depositional processes and other factors, such as shear banding and the intermediate principal stress, soils and rocks are typically cross-anisotropic. Strength anisotropy should be described by the proper anisotropic strength criterion. This paper presents an anisotropic unified nonlinear strength criterion to accurately characterize the strength anisotropy of geomaterials based on a unified nonlinear strength criterion (UNS). The anisotropic state variable in terms of a joint invariant and a unit stress tensor is brought into the UNS criterion to characterize the effect of the anisotropy. The new criterion had been illustrated in both the meridian and octahedral planes, leading it the oversimplification to describe strength anisotropy behaviors of soils and rocks under different loading conditions. Moreover, only conventional triaxial test is employed to calibrate the parameters of the new criterion. The results demonstrated the ability of the anisotropic strength criterion to be applied to a wide range of soils and rocks for true triaxial tests along with the complex stress condition in torsion shear tests. By comparing the predictions to test results reported in the literature, the new criterion proposed in this paper is able to provide excellent traits of the strength anisotropy for various geomaterials. [ABSTRACT FROM AUTHOR]