全断面隧道掘进机(TBM)在矿井开采中应用逐渐推广，坚硬围岩巷道与隧道施工过程中存在掘进困难、刀具损耗严重的问题，如何实现高强度高磨蚀性地层安全掘进对于指导地下工程建设和能源开发等具有重要意义。为此，提出低压磨料空射流切槽辅助滚刀破硬岩技术思路。基于低压磨料空气射流辅助滚刀破岩综合实验平台，研究不同切槽深度对滚刀破岩刀具受力和岩石破碎的影响。采用PFC数值分析不同切槽深度下刀具垂直载荷、裂纹扩展、比能耗和岩石应力场等变化规律，进一步解释切槽辅助滚刀破岩过程中刀具受力减小原因。形成以下主要结论：切槽底端是滚刀破岩过程应力集中区域，主裂纹从滚刀与岩石作用位置到切槽底端扩展贯通，当切槽深度大于8 mm后形成滚刀压痕处高、切槽底端低的“岩脊”状岩石破坏特征，随着切槽深度增加，岩脊高度逐渐变大。切槽后主裂纹与切槽边缘和岩石断面贯通，呈现三角状岩石破碎体，切槽深度越大，岩石块状破碎体的体积越大，同时滚刀最大垂直载荷越小，数值模拟结果与相关实验结果具有一致性。低压磨料空气射流切槽为20 mm时，滚刀最大垂直载荷为不切槽时的68%。切槽过后滚刀破岩过程中刀具两侧岩石应力减小，进一步使滚刀破岩过程刀具传递力的大小降低并朝着切槽底端传递，切槽起到移除侧向约束的作用，降低了刀具贯入的垂直载荷，形成大块状的岩石破碎体，从而减小破岩比能耗。

The application of full-face tunnel boring machine (TBM) in mine mining is gradually popularized. There are some problems in the construction of tunnels with hard surrounding rocks, such as difficulty in tunneling and serious tool loss. How to realize safe tunneling of high-strength and high-abrasion strata is of great significance for guiding underground engineering construction and energy development. Therefore, this paper puts forward a technical idea of low-pressure abrasive air jet grooving to assist hob to break hard rock. Based on the comprehensive experimental platform of low-pressure abrasive air jet assisted hob rock breaking, the effects of different cutting depths on the stress and rock breaking of hob rock breaking tools are studied. The PFC is used to numerically analyze the variation laws of vertical load, crack propagation, specific energy consumption and rock stress field under different grooving depths. These can further explain the reasons for the reduction of cutter force during the rock breaking process of grooving auxiliary hob. The main conclusions are as follows: the bottom of the notch is the stress concentration area in the process of rock breaking by the hob, and the main crack extends from the position where the hob interacts with the rock to the bottom of the notch. When the notch depth is greater than 8 mm, the rock failure feature of “rock ridge” with high indentation of the hob and low bottom of the notch is formed. With the increase of the notch depth, the height of the rock ridge gradually increases. After grooving, the main crack runs through the grooving edge and rock section. It will present a triangular rock fragment, and the deeper the cutting depth, the larger the volume of the rock fragment and the smaller the maximum vertical load of the hob. The numerical simulation results are consistent with the related experimental results. When the notch of low-pressure abrasive air jet is 20 mm, the maximum vertical load of hob is 68% of that without notch. After grooving, the rock stress on both sides of the cutter is reduced during the rock breaking process of the hob, which further reduces the transmission force of the cutter during the rock breaking process of the hob and transmits it to the bottom of the grooving. The groove removes the lateral constraint and reduces the vertical load of the cutter penetration. Large rock fragments are formed to reduce the specific energy consumption of rock breaking.