砂性地层下类矩形盾构机刀盘布置方案研究

Research on the Cutterhead Layout Scheme of Rectangular Shield Tunneling Machines in Sandy Strata

类矩形盾构机的切削断面形状并非中心回转对称,如何根据不同的地质条件选择适合的刀盘布置方案是类矩形盾构机研制的难点。依托杭州市轨道交通四季青站工程项目,对比在黏土地层与砂性地层2种施工条件下,类矩形盾构机的施工参数,发现盾构机在砂性地层中所受的推力、扭矩均较大,且存在较大冲击。原偏心多轴驱动仿形刀盘的结构形式,无法满足砂性地层中的施工工况。针对性地研究设计1种刀盘布置方案,采用2个X形大刀盘+2个可伸缩式圆形辅刀盘的组合切削形式,并增加带伸缩功能的辅刀盘驱动、切削盲区处壳体结构、土体改良等关键功能。该刀盘布置方案的研究与实践对提高类矩形盾构机的地层适应性有着重要意义。

The cutting section shape of a rectangular shield tunneling machine is not center rotation symmetry.How to choose a suitable cutterhead layout scheme based on different geological conditions is a difficult point in the development of a rectangular shield tunneling machine.Based on the Four Seasons Green Station project of Hangzhou Rail Transit,comparing the construction parameters of rectangular shield tunneling machines under two construction conditions of clay and sandy strata,it was found that the shield tunneling machines were subjected to significant thrust and torque in sandy strata,and there were significant impacts.The structural form of the original eccentric multi axis drive profiling cutter head cannot meet the construction conditions in sandy formations.Targeted research and design of a cutterhead layout scheme,using a combination cutting form of 2 X-shaped large cutterheads and 2 retractable circular auxiliary cutterheads,and adding key functions such as auxiliary cutterhead drive with retractable function,shell structure at cutting blind spots,and soil improvement.The research and practice of this cutterhead arrangement scheme is of great significance for improving the geological adaptability of rectangular shield tunneling machines.