关键词: 振动, 裂隙性黄土, 单轴压缩, 二元介质本构模型

Abstract: Uniaxial compression behavior of fissured loess after vibration was investigated by small-scale shaking table and uniaxial compression test. The test results show that the failure modes of fissured loess can be classified as four types, i.e. fracture failure, slip failure, coupled slip-fracture failure and compression-shear failure. The failure modes of fissured loess in uniaxial compression test are less affected by vibration, while it mainly controlled by fissure angle. Furthermore, vibration has little influence on the type and characteristic of the stress-strain curves, which constantly presents characteristics of strain softening. It is worth noting that the curves of loess samples with fissure angle of 45° show bimodal variation, and the second peak strength is generally larger than the first counterpart. The uniaxial compressive strength (UCS) approximately decreases linearly with growing vibration amplitude and frequency. With the increase of fissure angle, the UCS exhibits "double V" changes regardless of vibration parameters. A binary medium model is finally established, and it can well predict the stress-strain behavior and UCS of fissured loess after vibration.

Key words: vibration, fissured loess, uniaxial compression, binary medium constitutive model