In order to reveal the mechanism for the influence of the snowmelt infiltration on the non-equilibrium flow and stability of residual slope,the instability reason of a residual soil slope induced by snowmelt in Fujian Province was analyzed based on the unsaturated seepage model and the non-equilibrium flow model.Then,the influence laws of different diameters,distances,bending ratios and the lengths of macropores on moisture field and safety factor of the slope were also obtained based on non-equilibrium flow model.The results showed that non-equilibrium flow had a greater impact on the slope stability than that of considering unsaturated seepage.The theory of non-equilibrium flow could be adopted to reasonably interpret the instability mechanism of a residual slope induced by the snowmelt.With the increasing of the macropore diameter,the pore water pressure and the moisture exchange capacity between macropore domain and matrix domain would increase,but the priority conduction of water flow and stability for slope would decrease;the conduction route of water would be extended and water accumulation in the macropore would be decreased with the increasing of the length of the macropore.The length of the macropore played a certain part in the safety factor of slope.The bending ratio of the macropore had little influence on water content and safety factor of slope.There was a critical distance for the macropore distances which could lead to minimum safety factor of slope.The preferential flow of macropores would be restricted if the distance between macropores was too large,and the mutual superposition of non-equilibrium flow would decrease the pore water pressure in deep layer if the distance between macropores was too short.Therefore,the influence of non-equilibrium should be paid more attention for the instability of slope with macropore induced by snowmelt in the short-term frozen zone,especially in the distance between macropores and the length of macropore.
