A mechanics model of constant cross-section type disc cutter based on dense core forming mechanism

• Published in: Tunnelling and underground space technology Vol. 140; p. 105301
• Main Authors: Sun, Jingdong, Wang, Kai, Wei, Jin, Shang, Yong, Sun, Chaoyang, Ma, Fei
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.10.2023
• Subjects: Constant cross-section type disc cutter; Dense core theory; Mechanics model; Rock fragmentation; Stress field; Dense core theory; Constant cross-section type disc cutter; Stress field; Mechanics model; Rock fragmentation
• ISSN: 0886-7798; 1878-4364
• DOI: 10.1016/j.tust.2023.105301

•Solved the stress field of rock based on Boussinesq stress solution.•Revealed the formation mechanism of dense cores.•Proposed new force model for cutter based on dense core position.•The side force and normal force model is corrected by cutter spacing.•The influence of parameters on dense core position and cutter force is discussed. Based on the solution of Boussinesq problem, this paper studied the stress field beneath contact surface during the Constant Cross-Section (CCS) type disc cutter cutting. The feature of stress field indicated that dense core formed under the contact surface at a depth approximately equal to the half-length of contact surface. And the penetration and cutter thickness significant influence the dense core position. Based on Mohr-Coulomb criterion and the dense core position, a new cutter force model is proposed. And the side force and normal force model is corrected by cutter spacing according to linear correlation assumption. The accuracy and suitability for proposed model was compared with classic CSM model and numerous full-scale linear cutting machine (LCM) database collecting from the others’ researches. The research indicated that the proposed model can accurately predict cutting force in a wide range of rock mechanics parameters, especially on the rock with USC ≥ 40 MPa. In addition, the influence of main parameters on cutting force was discussed. This research offered fundamental insights into dense core forming and provided a theoretical basis for disc cutter design.