Research on the critical depth deterioration of the slip surface of soil slope in seasonal frozen area

Résumé

Soil slope is one of the main parts of the road engineering. In seasonal
frozen regions, shallow landslide hazards in soil slopes usually happen, which pose a
serious threat to road safety operations. During the melting process, there forms
stagnant water lubrication between the melting soil and freezing soil interface, which
constitutes the weak interface of landslide hazard. In order to study the shallow
landslide hazard of soil slope during the spring melt period in seasonal frozen areas,
considering that the freezing point of the brine is lower than pure water, a simulated
test method of the internal freezing and thawing interface of soil slope was designed.
The critical slip surface depths after freeze-thaw circles in different water content are
compared in the test, and the failure modes of the internal freezing and thawing
interface of soil slope are verified. Then the sliding face depth damage model of the
soil slope is put forward according to the experimental data. The results demonstrate
that with the increasing water content and freeze-thaw circle times, the value of
critical slip surface depth decreases gradually after freeze-thaw circles, the damage
model which is obtained from the experimental data fitting, would present more
reference of the slope design in the seasonal frozen area.