最新刊期

      LI Gang, TANG Yun, LIU Zhigang, HAO Lei, LIU Yang

      摘要：ObjectiveShear wave vibrators are susceptible to variations in coupling conditions during practical exploration, resulting in significant disturbances that lead to degraded excitation performance and unstable signal quality. Existing studies lack a systematic understanding of how coupling parameters influence the disturbance mechanisms and excitation effects of the vibrator. To address this issue, a shear wave vibrator-ground coupling dynamic model incorporating disturbance factors was developed, revealing the influence patterns of key coupling parameters on disturbances and output characteristics. This provides a theoretical basis for the structural optimization and stable excitation of shear wave sources.MethodsFirstly, based on elastic half-space theory and considering the disturbance effects induced by hydraulic overturning moments, a coupled vibration model of the shear wave source vibrator and the ground was established, and the validity of the proposed model was verified through tests. Subsequently, the influence patterns of coupling parameters on vibrator disturbances and system vibration output were analyzed on this basis.ResultsThe results indicate that, regarding vibrator disturbances, the plate area is the dominant parameter affecting disturbance sensitivity (accounting for 64% of total sensitivity), with significant nonlinear interactions existing among parameters; soil density accounts for nearly 0% of total sensitivity and can be regarded as a non-sensitive factor. In terms of vibration output, within the low-frequency range (5-20 Hz), an increase in the mass of the heavy hammer leads to insufficient output, while an increase in plate area contributes to enhancing output amplitude; a higher ground elasticity modulus can reduce energy dissipation. The findings provide a theoretical basis for suppressing shear wave vibrator disturbances and hold certain research value for improving vibrator excitation performance.  
      关键词：Shear wave controllable source;Coupling parameter analysis;Vibration characteristics;Vibration output;Disturbance analysis   
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      更新时间：2025-11-26

      ZHANG Shuang, YIN Guihu, CHEN Meiyu, YI Yali, WU Menglei

      摘要：ObjectiveAiming at the problem of significant vibration in the roller movable teeth due to long-term impact loads, a novel lattice roller movable teeth was proposed based on the hollow roller structure.MethodsFirstly, the impact resistance of four lattice structures was analyzed through equivalent stiffness prediction and impact tests, determining the optimal lattice structure and the structural parameters of the lattice roller movable teeth. Subsequently, simulation analysis was conducted to investigate the equivalent stress and vibration characteristics of solid roller movable teeth, hollow roller movable teeth, and lattice roller movable teeth. Finally, a vibration characteristic testing platform of roller movable teeth was established, and the vibration accelerations of different types of movable teeth were comparatively analyzed.ResultsThe results indicate that the proposed lattice roller exhibits a 28.72% reduction in equivalent stress compared to the solid roller and a 3.96% reduction compared to the hollow roller. Additionally, the peak vibration acceleration of the lattice roller movable teeth is significantly lower than that of the solid and hollow roller movable teeth, demonstrating excellent vibration damping performance. The test results align with the simulation trends, verifying the reliability of the simulation model and the accuracy of the test results. The findings of this study can provide a reference for the structural design of vibration reducing movable teeth.  
      关键词：Roller movable teeth;Lattice structure;Impact test;Equivalent stress;Vibration acceleration;Movable teeth transmission   
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      更新时间：2025-07-03

      LUO Zhaoyi, WANG Tianbo, WEI Minxiang, WU Jiang, XUE Wenshuai

      摘要：ObjectiveTo effectively address numerical instabilities and enhance optimization performance for achieving desirable results in continuum structural topology optimization problems, an improved strategy based on the variable density method is proposed.MethodsFirstly, in response to the limitations of the solid isotropic material with penalization (SIMP) model and the rational approximation material properties (RAMP) model in terms of penalty efficiency and convergence speed, an improved interpolation model was proposed. Secondly, the Sigmund sensitivity filtering method was employed to eliminate checkerboard patterns and mesh dependency phenomena. Finally, a grayscale suppression operator was designed and integrated into the optimality criterion (OC) method for updating design variables.ResultsNumerical studies have demonstrated that this scheme not only improves penalty efficiency and accelerates convergence speed but also eliminates completely grayscale elements, resulting in optimized structures with clear boundaries.  
      关键词：Variable density method;Topological optimization;Interpolation model;Grayscale suppression   
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      更新时间：2025-05-28

      ZHANG JianFeng, XU Fang, ZHANG Yan, HUANG XiaoBo, JIA ZhuoHan

      当前状态： 四校优先
      摘要：A correlation-regression method was proposed to solve the problem of low accuracy of parameter estimation and confidence limit calculation of the three-parameter Weibull distribution.The method was combined by the correlation coefficient method （Fu method） and the nonlinear regression method which makes full use of the convenience of Fu method and the excellent estimation effect of the nonlinear regression method in estimating the three-parameter Weibull distribution.In order to verify the effectiveness of the proposed method，the correlation-regression method，Fu method and Method combining maximum likelihood estimation and empirical formulae (referred to as the “MMPDS method”） were applied to the parameter estimation and confidence limit calculation of the data distribution of a certain alloy strength value with different sample sizes，and calculation consequence of different methods was compared and analyzed.Results show that the correlation-regression method has highest parameter estimation and confidence limit calculation accuracy among the above methods.When the sample size is less than 100，its advantage is more significant，and it can accurately calculate the parameters and confidence limits of the Weibull distribution.  
      关键词：Weibull distribution;Parameter estimation;Confidence limit   
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      更新时间：2024-06-27

      LIU YuZhuo, CAO LiXiong, WU JianGuo, LI HaiBo

      当前状态： 四校优先
      摘要：Reinforced shell structure is widely used in aerospace load-bearing structures because its high specific stiffness and specific strength.By considering the uncertainty and risk factors in the structural parameters，the Reliability-Based Design Optimization （RBDO） can avoid the overly conservative design of the structure and ensure its reliability and safety.An efficient RBDO method based on adaptive agent model was proposed.This method solves the problem of lightweight design of reinforced shell structure under buckling reliability constraints.The adaptive addition of sample points was implemented through the expected feasibility function criterion，and the discrete variables was continued by constructing piecewise functions.This increases optimization efficiency while ensuring the reliability of design results.Finally，the effectiveness of the proposed method is verified by comparing the RBDO results with the deterministic optimization results.  
      关键词：Reinforced shell;Reliability­based design optimization;Adaptive surrogate model;Expected feasibility function   
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      更新时间：2024-06-26
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