During the process of resin-anchored roof bolting in soft and broken surrounding rock, the fractures in the borehole wall can result in resin loss, affecting resin distribution and anchoring quality. In the paper, we developed a borehole repairing and strengthening device (BRSD) for resin-anchored bolt systems. Theoretical analyses, numeric al simulations, laboratory experiments and in situ test were performed to explore the resin flow characteristics given fractures, as well as the working principle of the device. The key parameters of the device were then optimized, and the working performance of the device was verified. The results indicate that the resin and the curing agent rapidly flow into the fractures subjected to bolt mixing. Increasing resin loss, fracture aperture, and number of fractures can cause the mean bonding stress to exceed the ultimate bonding strength of the interface between the resin and the surrounding rock. The developed BRSD has a good working performance. The resin mixer enables the resin to be discharged at a higher flow velocity from the resin container. The rib for resin daubing of the resin container can effectively and quickly daub the resin into the fractures. The device can reduce the number of fractures and the fracture aperture and form a regenerative borehole wall composed of rock fragments and resin in large broken areas. As a result, the anchoring length and the bearing capacity of the anchoring system are significantly improved. This study may provide a theoretical reference for the stability control and anchoring quality improvement of soft and broken surrounding rock.

在松软破碎围岩中进行树脂锚固顶板锚杆支护过程中，孔壁破裂会导致树脂流失，影响树脂分布和锚固质量。在本文中，我们开发了一种用于树脂锚杆系统的钻孔修复和加固装置（BRSD）。通过理论分析、数值模拟、室内实验和现场试验，探讨了裂缝条件下树脂的流动特性以及装置的工作原理。然后对装置的关键参数进行了优化，并验证了装置的工作性能。结果表明，螺栓混合后树脂和固化剂迅速流入裂缝中。树脂损失、裂缝孔径和裂缝数量的增加会导致平均粘结应力超过树脂与围岩之间界面的极限粘结强度。所开发的BRSD具有良好的工作性能。树脂混合器能够使树脂以更高的流速从树脂容器中排出。树脂容器的涂抹树脂筋可以有效、快速地将树脂涂抹到裂缝中。该装置可以减少裂缝数量和裂缝孔径，在大破碎区域形成由岩石碎片和树脂组成的再生井壁。从而显着提高了锚固系统的锚固长度和承载能力。该研究可为软破碎围岩的稳定性控制和锚固质量改善提供理论参考。