[Objective]Due to the engineering characteristics of loess,such as loose structure,low shear resistance and very sen-sitive to water,force and vibration,the bidirectional geoglids were used to improve the dynamic performance of soil before and after reinforcement of loess in Xining area.[Methods]Dynamic triaxial tests of reinforced loess under different conditions of rein-forced layer spacing,confining pressure and dynamic stress amplitude were carried out by GDS bidirectional dynamic triaxial test system.The effects of reinforced layer spacing on dynamic response characteristics of loess under cyclic load,such as dynamic strength,dynamic shear modulus and damping ratio,were analyzed,and the evolution law of dynamic response characteristics of reinforced loess was discussed.[Results]The result showed that the dynamic strain of loess increased with the increase of dy-namic stress,and the backbone curve showed a strain strengthening type.The backbone curve gradually changes from curvilinear to straight line with the decrease of the spacing between reinforced layers.With the decrease of the spacing between reinforced layers,the strength of loess increases.With the increase of confining pressure and the spacing between reinforced layers,the am-plitude shear stress of loess increases obviously,the dynamic shear strain decreases,and the damping ratio decreases obviously.[Conclusion]The result show that confining pressure and reinforced layer spacing significantly enhance the dynamic characteris-tics of reinforced loess,and there is an optimal reinforced layer spacing.The research result can provide reference for the road design of reinforced loess in Xining area.
关键词
土工格栅/动三轴模型试验/加筋间距/动力特性/循环荷载/变形/影响因素
Key words
geogrid/dynamic triaxial model test/the number of reinforced layers/dynamic characteristics/cyclic load/deforma-tion/influence factor
维普
万方数据