摘要
探究地质材料对刀具与地层相互作用规律的影响,有助于揭示盾构机在固结砂卵石地层等复杂地层中刀具切削机理和磨损失效机制。从刀具切削受力和切削效率入手,以不同地质材料类型和强度为控制变量,开展了刮刀和聚晶金刚石复合片(PDC)刀具直线切削试验。结果表明:①刀具受力大小和波动性随着地质材料中骨料硬度的增加而增加,骨料硬度的增加使得刀具切削过程更不连续;②最优切削深度随着骨料硬度增大而减小,素混凝土、陶粒混凝土和砂浆的最优切削深度分别为4,5 mm以及大于6 mm。③刀具受力大小及其波动性随地质材料强度增加而增大,在地质材料强度较高时刀具侵入更为困难,切削不连续性增加;④PDC刀具的最优切削深度随着地质材料强度增加而减小,切削C50、C40和C30时的最优切削深度分别为2,2.5 mm以及大于3 mm,圆形PDC刀具和锥形PDC刀具的切削效率变化特征类似,由于圆形PDC刀具切削多为拉应力破坏,导致切削比能更小。
Exploring the effects of geological materials on the interaction law between shield cutters and strata helps to reveal the cutting mechanism and wear loss mechanism in complex strata such as consolidated sand and pebble stratum.The linear cutting tests by using scraping cutters and Polycrystalline Diamond Compact(PDC)cutters are carried out with different geological types and strengths as control variables by analyzing the cutting forces and efficiency.The results show that:(1)The magnitude and volatility of cutting force increase with increasing aggregate hardness in the geological materials,and the increase in aggregate hardness makes the cutting process more discontinuous.(2)The optimum cutting depth decreases with increasing aggregate hardness,with optimum cutting depth of 4 mm,5 mm and more than 6 mm for plain concrete,ceramsite concrete and mortar,respectively.(3)The magnitude of cutting forces and their volatility increase with the strength of the geological material,and cutter intrusion is more difficult and cutting discontinuities increase at higher strengths of the geological material.(4)The optimum cutting depth for PDC cutters decreases as the strength of the geological material increases,with optimum cutting depths of 2 mm,2.5 mm and more than 3 mm for cutting C50,C40 and C30,respectively.The characteristics of cutting efficiency variations are similar for circular PDC tools and tapered PDC tools.As tensile stress damage is typical for circular PDC cutter,the cutting energy is smaller.
作者
邓龙传
李晓昭
赵鹏
许文涛
张弛
刘四进
DENG Longchuan;LI Xiaozhao;ZHAO Peng;XU Wentao;ZHANG Chi;LIU Sijing(State Key Laboratory of Intelligent Construction and Healthy Operation&Maintenance of Deep Underground Engineering,China University of Mining and Technology,Xuzhou 221116,China;School of Earth Sciences and Engineering,Nanjing University,Nanjing 210023,China;Yunlong Lake Laboratory of Deep Earth Science and Engineering,Xuzhou 221116,China;Shanghai Urban Construction Equipment Co.,Ltd.,Shanghai 200137,China;China Railway 14th Bureau Group Corporation Limited,Ji'nan 250101,China)
出处
《岩土工程学报》
北大核心
2025年第9期1936-1945,共10页
Chinese Journal of Geotechnical Engineering
基金
国家重点研发计划项目(2022YFC3003304)
江苏省自然科学基金项目(BK20241206)
徐州市科技项目(KC21312
KC21146)
江苏省卓越博士后计划项目(2023ZB228)。
关键词
盾构刀具
地质材料
刀具荷载
切削效率
PDC刀具
shield cutters
geological materials
cutting load
cutting efficiency
PDC cutter
