THE MECHANICAL PARAMETERS OF SURROUNDING ROCKS CONSIDERED IN TBM CUTTER DESIGN
TBM 刀具设计中围岩力学参数的选择

The mechanical property of surrounding rocks is the important factor which must be considered in TBM cutter design. At the same time, the factor has a close relation to the overall design of TBM and the feasibility of excavating tunnels with TBM. It is not perfect to select the parameter system whose key parameter is unconfined compressive strength (UCS). In the boring process, the rocks below the cutter are exerted on by vertical compressive stress and sink, and the rocks beside the cutter are compressed in the direction of face and swells. In the deformed rocks, the tensile or tensile-shear cracks appear. When the swelling areas between two cutters are superimposed, the deformed rocks are separated from the face. Under the cutter load, the larger the relative displacement between two points in the face is, the more advantageous to boring it is. The relative displacement is directly controlled by elastic modulus (E) and poisson′s ratio (μ). To sum up, in addition to UCS, E and μ should be taken into account in TBM cutter design.