Accurate inversion of geotechnical parameters is essential for assessing foundation-bearing capacity and stability, which directly impact structural safety and serviceability. Accurate prediction of load settlement behavior is crucial to prevent overdesign and underperformance, ensuring that foundations support anticipated loads without excessive deformation or failure. This paper presents an integrated optimization system combining ABAQUS (2022), Python (PyCharm21.3.3), and MATLAB (2022b) software, based on the Duncan-Chang (DC) model, for inversion of key geotechnical parameters. The ABAQUS UMAT subroutine customizes the DC model, facilitating its application in finite element simulations for soil-structure interaction analysis. To improve the optimization process, an adaptive genetic algorithm that dynamically adjusts crossover and mutation rates, thereby improving solution searches and parameter space exploration, is implemented. Key parameters of the DC model-the initial tangent stiffness (K) and nonlinear deformation characteristics (n) of soil-are inverted. The accuracy of this inversion is validated through comparisons with experimental pressure-settlement curves obtained from indoor bearing plate tests. Therefore, this optimization system effectively integrates intelligent algorithms with finite element analysis, serving as a reliable tool for precise geotechnical parameter inversion, with potential for improving foundation design accuracy, optimizing soil-structure interaction predictions, and improving the overall stability and safety of geotechnical structures.

To clarify the effect of various anchor cable failure modes on the dynamic responses of slopes, the FLAC3D software was redeveloped. Constitutive models of cable elements in different anchor cable failure modes were proposed and embedded into the main program of slope dynamic calculation. The axial force, acceleration, and displacement responses in different anchor cable failure modes were compared and analyzed. The effects of seismic parameters on the anchor cable failure modes were also investigated. A matching relationship between the ultimate load-bearing capacities of the anchorage, anchoring interface, and tendon was proposed. The results reveal that the seismic intensity causing anchor cable damage in anchorage failure mode (AFM) and grouting body failure mode is 0.2g-0.3 g lower than that in tendon failure mode. At the moment of failure, the stress released by the anchor cable in AFM is the highest, with the most evident instantaneous slope acceleration fluctuation. In the collaborative seismic design of the anchorage, anchoring section, and anchor tendon, the ultimate load-bearing capacities of the anchorage and anchoring interface should be increased by 1.8 times to match the tensile bearing capacity of the tendon. This study provides a reference for the seismic anchorage design of slopes and offers suggestions for selecting seismic design parameters for anchor cables.

To comprehensively consider the impacts of stratification, residual pore water pressure, soil nonlinearity, and boundary permeability on consolidation settlement of soft soil foundations for accurate prediction, a continuous drainage boundary condition is proposed in this study that reflects the residual pore pressure under multistage loading, and a nonlinear elastic constitutive model based on the double logarithmic model is adopted to account for the nonlinear consolidation behaviour of soils. A UMAT subroutine is developed based on the proposed boundary condition and nonlinear elastic constitutive model. Subsequently, the developed subroutine is compared with the built-in linear elastic soil constitutive model in ABAQUS and engineering examples. The application of continuous drainage boundaries in stratified foundations is analysed, as well as the influence of factors such as the loading rate and soil nonlinearity on consolidation settlement. The results indicate that, compared to the built-in model, the subroutine developed in this study can be employed to more accurately calculate the nonlinear consolidation of multilayered foundations under multistage loading. By adjusting the loading rate parameter alpha k, consolidation under different loading conditions can be predicted. Additionally, the proposed boundary condition simplifies the calculations for soft soil foundations with sand layers, providing a novel computational approach for the design of construction loading schemes and long-term settlement predictions in soft soil foundations.