世界核地质科学2023，Vol.40Issue(4)：992-1001,10.DOI:10.3969/j.issn.1672-0636.2023.04.010
适用于北山花岗岩的小直径盲井掘进机滚刀刃型初探
Preliminary Study on the Shape of Disc Cutters for Small-Diameter Blind Shaft Boring Machine Used in Beishan Granite
摘要
Abstract
In the construction of the underground research laboratory(URL)for geological disposal of high-level radioactive waste in China,the research and development of mechanical excavation equipment for disposition hole which is necessary for the site experiment needs to be carried out in the scientific research planning,and the selection of disc cutters for the excavation equipment of disposition hole in Beishan URL is one of the key issues that urgently need to be solved.The cross-sectional shape of the disc cutter ring directly affects the rock breaking efficiency and cutter consumption of the tunneling boring machine.This study designed and produced three different indenters with a diameter of 11 inches in flat,wedged,and round blades.An indentation test platform was developed and the indentation tests were conducted on large rock samples of Beishan granite.The acoustic emission(AE)monitoring system was used to study the damage mechanisms of the rocks under three types of indenters.The contact stress generated in the contact area between the disc cutter and the rock will cause damage inside the rock,and the larger the contact stress,the more conducive it is to promoting the propagation of internal cracks in the rock below the indenter.From the perspective of contact stress,the contact stress was relatively high under indenters of flat and round blades,making it easier for damage to occur inside the rock.The magnitude and distribution of acoustic emission energy can reflect the scale of internal crack propagation in rocks.The larger the energy,the larger the corresponding fracture scale.The number of acoustic emission events and energy consumption during the process of rock breaking by the wedge edge indenter were the highest,and the scale of rock fracture was the largest.From the perspective of the propagation characteristics of cracks,the development of vertical cracks was excellent under the action of the wedge-edge indenter,which was not conducive to the generation of rock fragments.During the process of rock breaking with a flat-edge indenter,the energy consumption was the smallest,and the scale of rock fracture was the smallest.From the perspective of the propagation characteristics of cracks,only a few cracks were generated at both sides of the blade under the action of the flat-edge indenter,and there were no transverse and lateral cracks that were conducive to the formation of rock fragments at the penetration depth of 2 mm.From the perspective of the propagation characteristics of cracks,longer lateral cracks were generated and rock fragments were generated on the surface of the rock under the action of the round-blade indenter.The 3D positioning results of acoustic emission showed that there were more radial cracks with smaller angles to the rock surface generated on both sides of the blade,which is more likely to cause rock fragments,consistent with the rock fragments generated under the round-blade indenter.The 3D positioning results of acoustic emission have good consistency with the cracks distribution displayed by fluorescent crack visualization method.Therefore,the round-blade disc cutter is suitable for small-diameter blind shaft boring machine for excavation of deposition holes.关键词
侵入试验/不同刃型滚刀压头/声发射技术/侵入力/裂纹分布Key words
indentation test/indenters with different shapes/acoustic emission monitoring technology/indentation force/crack distribution分类
建筑与水利引用本文复制引用
马亚楠,龚秋明,殷丽君,康乐..适用于北山花岗岩的小直径盲井掘进机滚刀刃型初探[J].世界核地质科学,2023,40(4):992-1001,10.基金项目
中国国家原子能机构核设施退役和治理专项(编号:科工二司[2021]830号)资助. （编号:科工二司[2021]830号）
