Stress influence between unit anchor bodies for compression dispersion-type anchored cables

There is stress influence between the unit anchor bodies for compression dispersion-type anchored cables. The first display of the influence is the stress superposition effect appearing in the compressive force transfer direction. The degree of the effect is different owing to the constraint force of rock around the hole on cement grouting body. The effect is very significant in weak rock mass with lower constraint force and not significant in hard rock mass with strong constraint force. The second display of the influence is that the tensile stress appears in the grouting body connected to pressure plates of the unit anchor bodies while the compressive stress superposition effect appears. The grouting body will be cracked if the stress is equal to the tensile strength, and the tension crack is not good for corrosion resistance of the anchored cables. In order to prevent the detriment to anchorage engineering, the optimization of the length of unit anchor body in the hard rock mass is suggested to avoid tension cracks, and the check of the strength of cement grouting body in the soft rock mass is proposed based on the stresses of the unit anchor body with the most serious stress superposition effect so as to avoid the damage of the grouting body and to enable the shear stress on cement grout-rock interface to be controlled.