Abstract:Shear lag model is employed to study the mechanism of prestressed anchoring cable considering the damage of rock mass and grouting material. By defining the shear damage variables of rock mass and grouting body,the damage evolvement equations corresponding to the basic principles of damage mechanics are proposed in the paper. The modified shear lag model is also given in the paper by combining the general shear lag model with shear damage of rock mass and grouting body. The model is applied to the research of resistance distribution and loading-deformation relationship of bond section of pre-stressed anchoring cable. Experimental results are in good coincidence with the theoretical prediction.