Based on hydrogeologic conditions and geomechanics model of highway slope in mountainous areas

a new catastrophic model on slope stability is established in consideration of the static water pressure of top splay fracture. Equations for calculating the critical water highness in the splay fracture and the critical rainfall intensity are developed by adopting cusp-catastrophic theory. The meteorological criterion of highway slope failure is put forward. At the same time

it is illustrated using the landslide on the No 316 national road in the southern Shaanxi Province. The results calculated by above model agree well with the observed ones

providing a new approach for the prediction of highway landslide.