Centrifuge model testing of a loess landslide induced by rising groundwater in Northwest China

• Published in: Engineering geology 2019-09, Vol.259, p.105170, Article 105170
• Main Authors: Zhang, Shuo, Pei, Xiangjun, Wang, Shanyong, Huang, Runqiu, Zhang, Xiaochao, Chang, Zhilu
• Format: Article
• Language: English
• Subjects: Centrifuge model test; Groundwater rise; Loess landslide; Static liquefaction; Tensile cracks
• ISSN: 0013-7952; 1872-6917
• DOI: 10.1016/j.enggeo.2019.105170

Considerable artificial irrigation in the Heifangtai area has caused the continued rise of groundwater levels, which has resulted in several large-scale landslides in the loess platform area. Considering the No. 13 landslide of Jiaojia in the Heifangtai area as a geological archetype, a series of centrifuge tests was conducted to study the deformation and failure characteristics of the slope due to the continuous rise in the groundwater level. Meanwhile, the pore water pressure, earth pressure, deformation, and evolution characteristics of the slope were monitored and recorded in real time. Furthermore, isotropically consolidated undrained triaxial testing (ICU) was conducted to investigate the static liquefaction of loess specimens, which was related to the slope instability. The centrifuge test results showed that a series of parallel and steep tension cracks at the top of the slope were present before the landslide, which was caused by the rising groundwater. The ICU experimental results showed that as the pore water pressure increased, strong strain softening and static liquefaction of saturated loess soils were found, which was related to the sudden destruction of the slope. •The sudden failure mechanism of loess slope is related to static liquefaction•Two kinds of landslide type are controlled by the thickness of overlying loess.•The ratio of pore water pressure to soil vertical effective stress plays an important role in early warning of landslide.•The continuous rising of the groundwater is an important cause of the group-occurring landslide in the Heifangtai area.•Controlling the level and rising rate of the groundwater are important for reducing the occurrence of the loess landslides in Heifangtai area.