Unsaturated hydro–mechanical coupling of fractured rock mass has important influenee on the strength and stability of rock mass. In recent years
the research of saturated hydro–mechanical coupling has achieved some advances
but saturated flow can’t be adopted simply in many practical projects. Based on the mechanical theory of DDA and fluid flow analysis of fractured network
unsaturated hydro–mechanical coupling analysis model is put forward naturally. And then taking a reservoir rock slope for example
the stability of rock slope is discussed when water level of reservoir falls. And it is shown that the safety factor is lower when the water level falls quckly and when considering coupling; it is consistent with the fact.