The strength and deformation characteristics of mudstone are important reference indexes in the engineering design and construction management.In order to analyse the effect of water-rock interaction and unloading on the strength properties and deformation characteristics of expansive mudstone,the sample of typical expansive mudstone in Nanning basin is chosen for the loading and unloading shear test and unloaded expansion ratio test.The intensity change rule of unloading mudstone is analyzed.And the influe...