Based on the description of the mechanical coupling at the interface between the bolts and the grout medium, an analytical model has been developed for fully grouted single bore multiple anchors. The shear stress of the interface attenuates exponentially with increasing distance when the deformation is compatible and the bolts are flexible. A series tests on rock bolts and bolts embedded in tension socketed pipe pile foundation have been taken to describe decoupling mechanism, interface shear strength distribution and fixed length requirement.Meanwhile, it is revealed that the pile end block effect plays a significant role in enhancing the reinforcement effect so that the shear strength takes a multi-section composite distribution with the change of soil characteristics, embedded length of pile and grout medium. It is also shown from the tests that the bond length with 6m in moderate weathered rock provides enough uplift resistance so as to serve theoretic and practical basis for construction. Based on the description of the mechanical coupling at the interface between the bolts and the grout medium, an analytical model has been developed for fully grouted single bore multiple anchors. The shear stress of the interface attenuates exponentially with increasing distance when the deformation is compatible and the bolts are flexible. A series tests on rock bolts and bolts embedded in tension socketed pipe pile foundation have been taken to describe decoupling mechanism, interface shear strength distribution and fixed length requirement. significant role in enhancing the reinforcement effect so that the shear strength takes a multi-section composite distribution with the change of soil characteristics, embedded length of pile and grout medium. It is also shown from the tests that the bond length with 6m in moderate weathered rock provides enough uplift resistance so as to serve theoretic and practical basis for const ruction.