Distribution of contact loads in crushed zone between tunnel boring machine disc cutter and rock

• Published in: Journal of Central South University Vol. 26; no. 9; pp. 2393 - 2403
• Main Authors: Shi, Yu-peng, Xia, Yi-min, Tan, Qing, Zhang, Yi-chao, Qiao, Shuo
• Format: Journal Article
• Language: English
• Published: Changsha Central South University 01.09.2019; Springer Nature B.V
• Subjects: Boring machines; Contact loads; Crushing; Cutting tools; Disc cutters; Engineering; Load distribution (forces); Machine tools; Metallic Materials; Penetration; Service life; Singular value decomposition; Stress concentration; Superposition (mathematics); Tool life; Tunnel construction; 卸荷区; 叠加原理; 接触载荷; contact loads; 盘形滚刀; non-loading area; disc cutter; superposition principle
• ISSN: 2095-2899; 2227-5223
• DOI: 10.1007/s11771-019-4182-8

The construction efficiency and quality of tunnel boring machines (TBMs) is largely determined by the service life of cutting tools, which is the result of contact loads in the crushed zone between cutter ring and rock. In this paper, a series of rock breaking tests were conducted with a 216 mm diameter disc cutter and concrete samples. Based on the superposition principle, the distribution of contact loads between disc cutter and rock were obtained by using the truncated singular value decomposition (TSVD). The results show that both the peak value and the whole numerical distribution of the radial strains on the cutter ring increase with the increase of the penetration. The distribution curves of the contact loads show an approximate parabola going downwards, which indicates contact loads are more concentrated. The front non-loading area with a ratio from 1.8% to 5.4% shows an increasing trend with the increase of penetration. However, the change of rear non-loading area is not obvious. It is believed that the conclusions have guidance for the study of rock breaking mechanism and manufacturing process of the disc cutter.