Precise finite element analysis of shear mechanical responses of anchor cables with C-shaped tube in roadway support
In order to prevent premature breakage of anchor cables under shear loads in support engineering,a structure named Anchor Cable with C-shaped tube(ACC)was proposed,which combines a C-shaped steel tube with anchor cables.Shear strengthening mechanism of this structure has not yet been fully revealed.A nonlinear finite element refined model of the ACC was established using ABAQUS software.The actual model of the seven-strand structure was adopted for the anchor cable,and shear resistance mechanism of ACC was studied considering the contact,failure,and other interactions of each component.The results show that in the initial stage of shearing,ACC forms an"S"shape of bending and symmetrical plastic hinge under the action of shear force at the shear plane and symmetrically distributed bending moment.Afterwards,the deformation is mainly caused by extension of the plastic hinge away from the shear plane and the stretching of the middle part of the anchor cable.Finally,the failure reason of ACC is the tensile-shear composite failure of the anchor cable,which is mainly tensile fracture.With the increase of the shear load,the C-shaped tube gradually closes within the bending range of the anchor cable,and works together with the anchor cable to enhance the overall bending stiffness of the structure.The slit opening and overall torsion of both ends of C-shaped tube are coordinated with the closure deformation of its middle part.C-shaped tube can make the distribution of the contact pressure more uniform between the structure and the concrete blocks,improving stress conditions.Partial concrete located at the interface of blocks is in a triaxial compression state.With the increase of the shear load,the bearing area gradually expands inside the concrete blocks,and the progressive failure of concrete occurs synchronously with the expansion of plastic hinge of ACC.
rock mechanicsdouble shear testprestressed anchor cablenumerical simulationplastic hingebreaking mechanism