岩石锚杆作为一种有效的加固方式已经广泛的应用于岩土和采矿工程中。通过托盘施加一定的预张荷载，即可以及时地限制围岩的早期变形，使其强度下降的幅度降低；又可以提高锚杆对围岩的约束能力，锚固强度得到提高。合理的预张荷载可以提高岩层的自撑能力，保证整个锚杆支护体系充分发挥支护效能。因此合理预张荷载的确定对锚杆设计具有重要的工程意义。本文基于围岩变形，通过弹、粘弹性理论，分别建立了围岩与锚杆相互作用的弹、粘弹性模型，推导出了预应力岩石锚杆剪应力及轴力分布公式，对合理预张荷载确定方法进行了深入的研究，取得的成果如下： (1) 对预应力岩石锚杆与围岩的作用机理进行了研究，其加固地下工程中的主要作用是对巷道围岩及时施加高预应力，限制围岩变形的发展，使巷道顶板形成具有较高承载能力的组合梁和组合拱，改善围岩应力场和岩体的受力状态，提高巷道围岩力学参数，使围岩整体作用加强。 (2) 基于岩石锚杆与围体微段界面摩阻力与它们之间的相对位移呈线性函数关系的假设，根据微段锚固体的受力平衡以及巷道围岩安装锚杆前后的应变变形，建立了岩石锚杆与围岩体之间相互作用的载荷传递微分方程，结合圆形巷道围岩的径向变形方程，分别推导了弹性岩体与粘弹性岩体在带托盘及无托盘条件下，岩石锚杆的剪应力与轴力的表达式，然后对影响应力分布的主要因素进行了系统的分析。 (3) 基于围岩变形，结合拉拔试验力学模型，推导出了预应力岩石锚杆的剪应力及轴力分布公式，提出了岩石锚杆合理预张荷载的确定方法。并结合算例，确定岩石锚杆合理预张荷载的大小。通过对锚杆应力分布的分析，可以得出：合理的预张荷载可以改善锚杆的受力状态，减弱锚杆剪应力集中，使锚杆受力更加合理，充分发挥锚杆支护性能，提高其锚固能力。 (4) 将以上研究成果应用于董家河煤矿锚杆支护设计，通过计算确定合理预张荷载的大小，然后进行现场试验，通过对比试验巷道在不同预张荷载条件下巷道支护的效果可以得出，施加设计预张荷载的试验段，与原支护试验段相比，巷道的变形量明显减小，巷道顶板离层也得到有效控制，表明了设计的预张荷载是合理的。

Rock bolt supporting as a kind of effective reinforcement way already widely used in geotechnical and mining engineering. The rock bolt that was applied pre-tension load by pallet on the one hand could actively restrain early deformation of roadway and reduce the magnitude of strength decline, on the other hand improve the bolt’s capacity to constrain the surrounding rock and improve the anchoring strength. The reasonable pre-stress could increase the rock’s self-supporting capacity and ensure the whole system of bolts give full play to support efficiency. Therefore the determination of the reasonable pre-stress is greatly significant for anchor design in projects domain. Based on the deformation of surrounding rock, combined with the elastic theory and visco-elastic theory, the elastic and visco-elastic model of the interaction of surrounding rock and bolt was set up, the pre-stressed rock bolt’s stress distribution function was carried out and the method to determine the reasonable pre-stress of rock bolt was putted forward. Results obtained are as follow: (1) The main function of pre-stressed rock bolt support is to provide high pre-stressed early for surround rock, which can limits the further distortion of surrounding rock. Pre-stressed rock bolt support can form a combined beam structure, reduce roof tensile stress area and roof distortion, ameliorate surrounding rock stress distribution and enhance the stability of entry. (2) On the assumption of the relation is a linear function between the small section of bolt and the country rock mass, the bolt’s load transfer differential equation was established according to the stress equilibrium in a small section of a bolt and the rock mass deformation before and after bolt assembling under the interaction between country rock mass and bolt. And combining the radial deformation of roadway rock mass, the function of the shear stress and axial force were established with the elastic and visco-elastic rock on the base of the pallet. And then the main factors which influence the distribution of bolt stress were analyzed exactly. (3) Based on the deformation of surrounding rock, combining with the mechanics of the pull-out test, the pre-stressed rock bolt’s shear stress distribution function and axial force function under the pre-stress was carried out and the method to determine the reasonable pre-stress of rock bolt was putted forward. And combining a example to determine the size of the reasonable pre-stress. Though analyzing the distribution of bolt stress, it was gotten that the reasonable pre-stress could improve the bolt’s stress state, decrease the bolt’s stress concentration, give full play of the bolt’s support performance and improve the anchorage strength. (4) The research results on the above were applied in the bolt support design of Dongjiahe mine coal. The size of the reasonable pre-stress was determined by calculating, and then the field trial was done. By comparing the supporting effect in the testing roadway under the condition of the different pre-stress, it was obtained that the deformation and separation of roadway roof was decreased significantly. It was demonstrated that the pre-stress designed was reasonable.