Fractured rock mass under loading and unloading environment is ubiquitous with the influence of natural geological and artificial disturbance; the fracture surface geometry and the influence of unloading environment on fracture seepage characteristics can not be ignored in actual engineering. Using the methods of combining experimental and numerical simulation

to do the seepage flow experimental of fractured core with different roughnesses under loading and unloading

the thermo-hydro-mechanic coupling seepage flow system are used

to import the three dimensional morphology of fracture surface obtained by laser scanning into ABAQUS

the self-developed program is introduced. Both experimental and numerical simulations show that: The width and permeability of rough fracture decreases with the increase of load. With the increasing of load

the contact stiffness of fracture increases and the sensitivity of width and permeability decrease. The plastic deformation caused by points contact can not be recovered

The increasing amplitude of width and permeability of fracture decrease in stage of unloading

and less than that in loading stage under same conditions. Permeability

width and roughness of fracture were positively correlated. The greater the contact stress distribution is

the greater the roughness is. The field of flow in the crack is flow around islands

the greater the roughness

the phenomenon of flow around islands more obvious.