截齿刀具切削混凝土连续墙试验研究  

Impact of Tool Taper and Arc Length on Cutting Efficiency of Pick Cutter on Concrete Diaphragm Wall

作　　者：庄欠伟 张福兵 张弛 朱龙海 ZHUANG Qianwei;ZHANG Fubing;ZHANG Chi;ZHU Longhai(School of Mechanics and Engineering Science,Shanghai University,Shanghai 200444,China;Shanghai Tunnel Engineering Co.,Ltd.,Shanghai 200238,China)

机构地区：[1]上海大学力学与工程科学学院,上海200444 [2]上海隧道工程有限公司,上海200238

出　　处：《隧道建设（中英文）》2021年第8期1307-1314,共8页Tunnel Construction

基　　金：上海市启明星计划项目(20QB1401800)。

摘　　要：基于在混凝土连续墙切削中的刀具损伤问题,借鉴采煤领域中的切割技术并针对不同刀头锥度和刀尖弧长设计4种不同的截齿刀具。先通过仿真确定切削轨迹,设定相邻切削轨迹间距大于18 mm;随后对C35混凝土进行切削试验。试验结果表明:1)刀具弧长和刀具锥度的减小可使切削合力下降,但刀具锥度的影响性小于刀具弧长;2)正压力分力受刀具弧长和刀具锥度的影响均较小;3)切向力分力受刀具弧长影响较大,刀具弧长的减小可以减小切向力以达到降低转矩的目的,但易造成切削效率的下降。基于前期试验结果兼顾考虑刀具耐久性,选用锥度为40°、弧长为5 mm的刀具作为试验刀,并对C35玻璃纤维筋混凝土进行模拟盾构试验,对比立体化布置后的贝壳刀切削效果。对比发现:截齿刀具有效解决了采用贝壳刀切削时刀盘卡死的问题,切削能力优于立体化布置后的贝壳刀,有效控制了转矩峰值,但截齿刀具刀身体积过小,易出现整体剪切断裂。To limit the tool damage of shield when cutting the concrete diaphragm wall, four types of pick cutters are designed according to the cutting technique in the coal mining industry using different tapers of the cutter head and arc lengths of cutter tip. The cutting trace is determined via simulation, and the distance between the two adjacent cutting traces is set over 18 mm. Then, the cutting test is conducted on C35 concrete. The following are the test findings:(1) The cutting force decreases with the decreasing tool arc lengths and taper, and the impact of tool taper is smaller than that of tool arc length.(2)The tool arc length and taper slightly affect the positive component force.(3) The tool arc lengths significantly influences the tangential component force;the tangential force and torque decrease with the decreasing tool arc length, thus decreasing cutting efficiency. The cutting tool with a taper of 40° and a arc length of 5 mm is chosen as the experimental tool to perform a simulation test of C35 glass fiber reinforced concrete based on preliminary experimental findings and tool durability. The cutting effect of the designed tool is compared to that of the three-dimensional shell cutter, and the comparative findings demonstrate that the pick cutter can effectively avoid the cutterhead jamming when using shell cutter;its cutting ability is better and the peak torque is efficiently controlled. However, the pick cutter is too small, leading to a total shear fracture.

关 键 词：截齿刀具 刀具锥度 刀具弧长 混凝土连续墙 切削效率 切削试验 

分 类 号：U455.43[建筑科学—桥梁与隧道工程]