Development and application of a full-scale mechanical rock-cutting platform for measuring the cutting performance of TBM cutter

With the massive development of mechanical equipment for underground space construction, understanding the cutting mechanism and measuring the cutting performance of various cutters used in tunnelling boring machine prior to the construction is vital for increasing tunnelling efficiency and reducing cost. Mechanical rock-cutting tests have been an indispensable method for investigating the cutting characteristics, which can be effectively used for guiding the mechanical excavation of underground engineering. In this paper, a novel full-scale cutting platform developed by Shanghai Shield Design and Experimental Research Center Co., Ltd is introduced. The rock types, rock structure types, cutter types, cutting radius, rotation speed, penetration depth, cutting modes, cutter spacing and cutter installation angle are considered and integrated into the design of cutting platform. Specifically, different cutters, including disc cutters, scraper cutters, shell cutters and pick cutters, can be considered in this platform. Moreover, the circular cutting mode can be conducted with cutting diameter ranging from 0 to 6.2 m, and the arc cutting method is originally proposed to perform a rotary cutting test with cutting diameter above 6. 2 m. Notably, a laser measurement method is newly performed to measure the rock surface profile and calculate the rock cutting volume in the rotary cutting mode. The rock-cutting platform consists of mechanical system, hydraulic system, cutterhead system, control system, data sensing and acquisition system. The measuring reliability and accuracy of the newly designed rock-cutting platform and laser measurement is experimentally verified by the rotary cutting tests on granite and mortar using disc cutter and scraper cutter. A critical cutting radius of 1000 mm for side force is acquired, and the effects of cutting radius and cutting depth are initially investigated. The development of the full-scale rock-cutting platform is an effective measurement method for cutting performance, which can provide data support for optimization of cutterhead layout and determination of working parameters.