## 6 Analysis of Influencing Factors of Rock Bolt Body Deformation
### Analysis of Simulation Results
#### 6.2.2 The Force Analysis of Rock Bolts  
During the simulation process, the axial force and shear force at each position of the anchor bolt body were monitored in real time to reveal the deformation and force characteristics and influencing factors of the anchor bolt body under the action of the layered composite roof. Figures 15 and 16, respectively, show the axial force and shear force characteristics of the anchor bolts with different strengths of the surrounding rock and structural planes. It can be concluded from Figures 15 and 16 that in Test I, the axial force and shear force of the bolt body increased significantly at the \(2^{\#}\) interface, so the bolt body underwent obvious deformation at the \(2^{\#}\) interface, while no obvious deformation occurred at the \(1^{\#}\) interface, and the shear force condition also indicated that the bolt body was not subjected to shear at this point. In Test II, the axial force of the bolt body increased significantly at the \(1^{\#}\) interface, and the shear force of the bolt body also indicated that the bolt body was subjected to obvious shear at the \(1^{\#}\) interface. The \(2^{\#}\) interface was located in the non-anchored section of the anchor bolt, and it was impossible to determine whether the axial force increased nearby, but the shear force condition of the bolt body indicated that the bolt body was subjected to shear force at this point. Comparing the bending deformation conditions of the anchor bolts near the \(1^{\#}\) and \(2^{\#}\) interfaces, the deformation degree of the anchor bolt near the \(1^{\#}\) interface was smaller than that near the \(2^{\#}\) interface, but the shear force of the anchor bolt near the \(1^{\#}\) interface was higher than that near the \(2^{\#}\) interface, indicating that when the surrounding rock strength was higher, the anchor bolt could mobilize a greater deformation resistance with a smaller deformation. In Test III, the axial force of the bolt body increased significantly at the \(1^{\#}\) interface, and the shear force of the bolt body also indicated that the bolt body was subjected to obvious shear at the \(1^{\#}\) interface. No obvious deformation occurred at the \(2^{\#}\) interface, and the shear force condition also indicated that the bolt body was not subjected to shear at this point. In Test IV, the axial force of the bolt body did not increase significantly at the \(1^{\#}\) interface, and the shear force of the bolt body indicated that the bolt body was not subjected to obvious shear at the \(1^{\#}\) interface. However, the shear force of the bolt body at the \(2^{\#}\) interface increased significantly, and the bolt body also underwent obvious shear deformation. Analyzing the above four tests, when the strength of the structural plane was small, the rock strata near the structural plane all underwent lateral dislocation, indicating that the strength of the structural plane was the primary factor controlling the lateral dislocation of the structural plane. Secondly, when the strength of the surrounding rock above and below the structure differed greatly, the structural plane was also prone to lateral dislocation, which was caused by the uncoordinated deformation of the rock strata above and below the structural plane. When the weak rock layer was located below the structural plane, the lateral dislocation of the structural plane was more likely to occur. Figure 15: Axial Force Characteristics of Rock Bolts with Different Surrounding Rock and Structural Plane Strengths. To sum up, the rock bolt and the roadway surrounding rock have an interactive relationship. In addition to the strength of the surrounding rock itself, the strength of the bedding of the roadway surrounding rock structural plane is also an important factor affecting the force, deformation and failure of the rock bolt. [PERSON] et al. [31] used a linear drop model once to analyze the stress distribution characteristics of the rock bolt under the opening of the bedding rock mass.