锚固孔扩孔锚固作为增强锚杆(索)对煤矿软弱围岩巷道支护效果的技术举措，对提升煤矿软弱围岩巷道主动支护质量及安全水平发挥了重要作用，然而，扩孔施工也明显增大了扩孔位置锚固孔的尺寸，导致按照锚杆(索)常规树脂锚固施工方式进行施工时扩孔区锚固剂固化及充填效果不理想等问题，显然这不利于锚固孔扩孔锚固性能的充分发挥。为明晰锚固孔扩孔锚固时扩孔区锚固问题及其影响，并寻找有效的解决途径，以确保锚固孔扩孔条件下锚杆(索)的锚固性能，采用数值模拟及实验室实验相结合的方法开展了系统研究。研究结果表明：施工过程中树脂锚固剂弯折(曲)进入扩孔区使锚索无法对它进行有效搅拌及破碎，以及扩孔位置锚固孔体积的增大使得锚固剂不能有效充满，是导致扩孔区锚固问题的主要原因；锚索拉拔模拟结果显示扩孔区锚固缺陷对锚索的锚固性能及锚固系统的失效形式有较大影响；为改善扩孔区的锚固效果，提出了锚固孔底部扩孔区锚固效果保障方法，并实验验证了该方法的有效性，实验结果表明该方法有效确保了软弱围岩锚固孔底部扩孔区的锚固效果，增强了锚索的锚固性能。本研究有效解决了锚固孔扩孔区的锚固问题，有助于煤矿软弱围岩条件下锚索高强支护能力的充分发挥，为确保锚索对软弱围岩巷道支护效果提供了技术途径。

As a technical measure to enhance the support effect of bolts (cable bolts) on weak surrounding rock roadway in coal mine, the borehole reaming has played an important role in improving the quality and safety of active support for weak surrounding rock of coal mine roadway. However, the reaming construction also significantly increases the size of the boreholes at the reaming location. This leads to problems such as the curing and filling effect of the resin in the borehole area reamed is not ideal when the construction is carried out in accordance with the conventional resin anchoring construction method of the bolt, which is obviously not conducive to the full play of the anchoring performance of the borehole reaming. In order to clarify the anchoring problem and its influence in the reaming area of the borehole and find an effective solution to ensure the anchoring performance of the bolts (cable bolts) under the reaming condition of the borehole, a systematic study was carried out by combining numerical simulation and laboratory experiments. The results show that the bending (curving) of the resin cartridges into the reaming area during construction process, which makes it impossible for the cable bolt to effectively mix and break resin cartridges, and the increase of the volume of the borehole at the reaming position makes the resin unable to fill effectively, they are the main reasons for the anchoring problems in the reaming area. The simulation results of cable bolt pull-out show that the anchoring defects in the reaming area have a great impact on the anchoring performance of the cable bolt and the failure mode of the anchoring system. In order to improve the anchoring effect of the reaming area, this paper proposes a method to guarantee the anchoring effect of the reaming area at the borehole bottom, and the effectiveness of the method is verified by experiments. The experimental results show that this method can effectively ensure the anchoring effect of the reaming area at the bottom of the borehole in weak surrounding rock, and enhance anchoring performance of the cable bolt. This study effectively solves the anchoring problem in the reaming area of the borehole, which is helpful to give full play to the high strength support ability of the cable bolt under the condition of weak surrounding rock in the coal mine, and provides a technical way to ensure the support effect of the cable bolt in weak surrounding rock.