The Study On The Key Issues Of Disc Cutters’s Layout Of The Hard Rock Tunnel Boring Machine

Hard rock tunnel boring machine (TBM) is a kind of mechanical constructionequipment which is used to full-face excavation in underground engineering project.It is widely used at home and abroad because of its lots of advantages, such as fastand efficient excavation, high safety and reliability, good construction quality.Cutterhead is one of the key parts of the hard rock tunnel boring machine; differentgeological formation should be adopted different cutterhead structure and cutterlayout method. The reasonable of the cutters’ layout is related to the workers workingenvironment, construction equipment operation quality, and it affects the speed andeffectiveness of the machine directly. The paper studied the key issues of the disccutters’ layout of the TBM, the main contents are as follows.(1) The cutting mechanism of TBM disc cutters has been researched. A newmethod, the smoothed particle hydrodynamics (SPH), was used to study the rockcrack initiation, expansion process under the disc cutters’ action. The effects of thecutter spacing and the loading method on the rock chipping process have been studied.The study showed that the rock was mainly tensile failure under the disc cutters’action.(2) The cutter spacing, different phase angle are the key issues of layout of disccutter, and the issues were studied in this paper. The rotary rock cutting process underdifferent cutter space, phase and the installation radius of the disc cutter wereresearched. The relationship between cutter space, phase, installation radius and thecutters’ force, rock chip quality were analyzed, and the optimum cutter space andphase were determined based on the minimum principle of the specific energy. Finally,the different cutting rock methods were discussed; and the cutters; force wereanalyzed in detail, the result showed that the effect of rock fragmentation was betterunder disc cutters combination rather than disc cutter broken rock alone.(3) The parameters according to the simulation were used to calculate theclassical force prediction models, and the calculated results were compared with thesimulation results. The linear cutting force prediction model of Colorado school ofmines was more close to the simulation results.