动荷载下EPS颗粒混合轻量土的动强度特性试验研究

Research on Dynamic Strength Properties of Light Weight Soil Mixed with EPS Beads Under Cyclic Loading

为研究EPS颗粒混合轻量土的动强度特性,以黄土作为原料土制备试样,对EPS颗粒掺入比为0.14%、0.31%、0.54%、0.86%、1.31%,水泥掺入比为10%、15%、20%的EPS颗粒混合轻量土进行室内动三轴试验。试验结果表明:EPS颗粒混合轻量土在动荷载作用过程中,动应变增长比较平稳,没有出现变形急速陡转的情况,而且压应变明显大于拉应变。选择5%压应变作为破坏标准进行分析。随着围压和水泥掺入比的增大,EPS颗粒混合轻量土动强度增大;随着EPS颗粒掺入比的增大,EPS颗粒混合轻量土动强度减小。相比较于本试验配制的重塑黄土动强度,不同配比的EPS颗粒混合轻量土的动强度增大幅度为20.8%~232.9%。该结论可为EPS颗粒混合轻量土在地基改良方面的应用提供参考和理论支持。

To study the dynamic strength characteristics of light weight soil mixed with EPS beads,taking loess as raw material soil,the dynamic triaxial tests of light weight soil are tested under 5 different EPS contents by weight（ 0.14%,0.31%,0.54%,0.86%,1.31%）,and 3 different cement contents by weight（ 10%,15%,20%）. The results show that the dynamic strain is relatively stable,there is no sudden change of deformation,and the compressive strain is obviously more than that of tensile strain during the cyclic loading. 5%compressive strain is chosen as the failure criterion. With the increase in confining pressure and cement content,the dynamic strength of mixed light soil increased. With the increase in EPS ratio,the dynamic strength of the mixed light soil decreased. Compared with the dynamic strength of remolded loess,the increased range of dynamic strength of light weight soil under different mixed ratio is 20. 8% ～ 232. 9%. It indicates that light weight soil can be used in ground improvement on some special subgrade.