Abstract: In view of the concealment and abruptness of loess collapse, the early identification and prediction of loess collapse were investigated, and corresponding emergency prevention measures were proposed. The characteristic factors for early identification of loess collapse were first of all extracted based upon summary on the inducing factors of loess instability via classifying the failure modes of loess in Shanxi Province. Subsequently, the risk of loess collapse was analyzed semi-quantitatively by using comprehensive index method, and on the basis of the quantitative result, the criterion for rating the risk of loess collapse was proposed, and emergency prevention measures were presented corresponding to different risk levels. Research result showed that: (1)the deformation and destruction of loess collapse mainly happened in four kinds of rock and soil structure combination and five typical damage contact surfaces;(2)the risk of loess collapse can be divided into four levels, namely, high level, medium level, relatively low level, and low level, each should be followed with corresponding emergency response measures such as emergency avoidance, disaster monitoring, emergency investigation, exploration and treatment;(3)early warning and forecasting measures for geological hazards can be directly taken when the deformation indication score reaches “high risk” of the judgment level.

Key words: loess collapse, geological disaster, failure modes, early identification, factors of hazard identification