粉细砂-砾岩复合地层条件下大直径越江盾构刀具磨损

为了确保大直径泥水盾构下穿江底复合地层安全顺利施工掘进,对于刀盘刀具磨损的预测和监测至关重要。本文以武汉地铁8号线黄浦路站～徐家棚站越江盾构隧道工程为背景,结合现场调研与磨损数据分析,首先根据不同地层中的刀具磨损特点进行磨损情况分类,并从地质、施工等角度对磨损原因进行了归纳,将整个越江过程中的刀具磨损分为8类,并认为滚刀非正常磨损主要由三大主要原因构成；然后基于磨损系数,对不同刀具在不同地层以及不同位置的适应性进行了分析。结果表明：(1)在复合地层中刀具磨损大小排序为撕裂刀>滚刀>刮刀>齿刀,且刮刀对硬质中胶结砾岩适应性较差,对强风化以及弱胶结砾岩适用性优于其他刀具。(2)中胶结砾岩的存在会加剧磨损,且会给大直径盾构边缘刀具带来更大的磨损影响,而强风化砾岩和弱胶结砾岩则对磨损变化影响不大。

Study on Cutter Wear of Large Diameter Cross-river Shield Tunneling in Silty Sand-Conglomerate Composite Stratum

In order to ensure the safe construction of large-diameter slurry shield tunneling under river bottom composite stratum, it is very important for the prediction and monitoring of cutter wear. Based on the Wuhan Metro Line 8 Huangpu Road Station ~ Xujiapeng Station cross-river shield tunnel project, the field investigation and data analysis has been conducted. First, the wear conditions were classified according to the characteristics of cutter wear in different geological situation, and the causes of wear has been summarized from the perspectives of geology and construction situation. The cutter wear during the entire tunneling process when crossing the river was divided into 8 categories, and it is considered that abnormal wearing of the hob is mainly composed of three main reasons. Then based on the wear coefficient, the adaptability of different kinds of cutters in different stratums and different installation positions is analyzed. The result shows that (1) The order of cutter wear in the composite formation is tearing knife> hob> scraper> tooth knife, and the scrapers showed poor adaptability to hard medium cemented conglomerate, also its applicability to strong weathering and weak cemented conglomerate is better than other tools. (2) The presence of medium-cemented conglomerate will aggravate the wearing and will have greater wear impact on the cutters installed on the edge of large-diameter shield, while strongly weathered conglomerate and weakly cemented conglomerate have little effect on the cutter wear.