荷载-降雨耦合作用下土石混填路基力学性能劣化机理研究OA

The coupled effects of traffic loading and rainfall infiltration pose a great threat to the stability of embankments filled with soil-rock mixture.To reveal the failure mechanism of the embankment,we conducted a comparative analysis under both baseline and rainfall conditions,based on the typical em-bankment structure of mountain highways,using a combined approach of scaled indoor physical model tests and numerical simulations.An integrated monitoring system was deployed to analyze the evolution of moisture content,mechanical response,and deformation patterns of the embankment under static load-ing.The results indicate that rainfall infiltration reduces the ultimate bearing capacity of the embankment from 550 kPa to 450 kPa,corresponding to a reduction of 18.18%.The failure mode shifts from overall shear failure under baseline condition to localized crushing failure with no evident sliding surface,which is induced by fine particle migration and increased pore water pressure under rainfall condition.Both soil pressure and settlement distributions exhibit significant spatial heterogeneity,with pronounced boundary constraint effects.Based on these findings,it is recommended that embankment design in rainy regions should incorporate a bearing capacity reduction coefficient of 18%-20%,and implement real-time mois-ture monitoring at critical sections.Furthermore,to avoid fine particle loss and enhance water stability,the proportion of aggregates larger than 40 mm should be controlled within 55%-60%for the establish-ment of a stable rock structure.The outcomes of this study can provide quantitative references for the de-sign and disaster prevention of soil-rock embankments.