The contact pressure distribution between the disc cutter and rock surface plays an important role in cutter force prediction, cutter optimization and performance prediction of the tunnel boring machines. The present study presents a preliminary investigation of the direct measurement of the contact pressure between cutter and rock surface using the Discrete Element Method. Firstly, to realistically reproduce the cutting process and to reduce the simulation time, various modelling set up methods are conducted and discussed to choose a proper method. Secondly, contact pressure distribution are fitted by different distribution functions. Gauss distribution and Lorentz distribution were found more suitable to describe the distribution. Thirdly, it is found that the maximum contact pressure is only related to rock properties and slightly affected by other factors like cutter speed or penetration depth. And the contact angle corresponding to maximum contact pressure can be easily calculated by Cutting Coefficient, which is the ratio of rolling force to normal force. The cutting process is also greatly influenced by the presence of discontinuities. The maximum contact pressure is reduced when bedding plane is inclined to the cutting direction, which indicates the best cutting performance. These findings can provide insights and improve the understanding of the fragmentation mechanism beneath the cutter and cutter force prediction in the field.

圆盘刀具与岩石表面的接触压力分布在隧道掘进机的刀具受力预测、刀具优化和性能预测中起着重要作用。本研究对使用离散元方法直接测量刀具和岩石表面之间的接触压力进行了初步研究。首先，为了真实地再现切割过程并减少模拟时间，对各种建模方法进行了讨论，以选择合适的方法。其次，接触压力分布由不同的分布函数拟合。发现高斯分布和洛伦兹分布更适合描述这种分布。第三，发现最大接触压力仅与岩石性质有关，受刀具速度或穿透深度等其他因素的影响较小。与最大接触压力对应的接触角可以很容易地通过切割系数计算，即轧制力与法向力的比值。切割过程也受不连续性的影响很大。当床层平面与切削方向倾斜时，最大接触压力减小，表明切削性能最好。这些发现可以提供见解并提高对刀具下方破碎机制和现场刀具力预测的理解。