考虑应力依赖的路基压实"轮-土"振动互馈特性与施工质量智能控制研究OA

During subgrade compaction,the dynamic resilient modulus of soil exhibits spatiotemporal variations.Existing studies typically assume this parameter to be constant,which cannot accurately reflect the true mechanical properties of subgrade soil during compaction.Moreover,commonly used compaction meter value(RCMV)cannot effectively indicate compaction quality.To address these issues,a dynamic deflection equivalency-based approach was proposed to determine equivalent resilient modulus of to-be-compacted subgrade soil considering stress dependent nature.A finite element model was constructed,and the corresponding VUMAT and VUSDFLD subroutines were developed.Comparative analysis of field measurements and numerical simulation data validated the prediction accuracy of numerical model.Subsequently,an energy index,called energy ratio value(RERV),was proposed to assess compaction quality,taking into account the loading sequence.Furthermore,a sensitivity analysis of factors influencing compaction quality(i.e.,roller deadweight,rolling speed,excitation force,and excitation frequency)was conducted.The results indicate that compared to field measured degrees of compaction,stress-dependent numerical model achieves a coefficient of determination(R2=0.75),which is significantly higher than that of non-stress-dependent model prediction(R2=0.39).This demonstrates the importance of considering stress dependence for compaction quality control.R2 between RCMV and compaction degree is only 0.52,while that between RERV and compaction degree reaches 0.67.Among the analyzed factors,rolling speed is the most significant variable affecting compaction quality.This research provides a theoretical basis and methodological support for further research on intelligent control of subgrade compaction.