Papers by Author: Hai Feng Zhao

Abstract: To realize accurate prediction of disk cutter performance and determine the crucial parameters in the design process of TBM (Full face tunneling boring machine), a new performance forecasting method of the circular blade cutter is presented, which integrates the parameters of breaking rock such as rock, disc cutter and construction. Furthermore, the second derivation in the process of breaking rock is considered, a new comprehensive performance forecasting model of the circular blade cutter is established based on the Coulomb-Mohr failure criterion. On the basis, the existed performance forecasting models of disc cutter such as Liner Cutting and CSM, and the performance forecasting model of disc cutter presented this paper are analyzed and calculated, according to Colorado linear cutting experiment. The calculation results indicate the prediction accuracy of the performance forecasting model presented in this paper is greatly improved, comparing with the existed models (such as CSM, linear cutting). Finally, the influences of the parameters (rock, disc cutter and construction) are analyzed, which provides for the overall design of TBM cutter and construction with some scientific basis.

Abstract: This paper presents a novel model of lay out of cutter head of TBM(tunnel boring machine). Rock-broken mechanism during the operation of the cutter head is analyzed to study the layout of cutters. A model of the cutters under the action of forces during TBM’s working has therefore been developed, thus proposing a scheme to improve the rock breakability of TBM’s cutter head on which the cutters are lay out. Then, a nonlinear multi-objective mathematical model with complex constraints is developed, with an optimization program provided via an intelligent algorithm for the layout design of cutters on the cutter head of a TBM. The cutter head of an EPB6.28 TBM, an optimized design is given to set up a prototype with digitized cutter head, to which a simulation is done for the verification of equilibrium of forces. Comparing analytically the cutter wear and equilibrium of forces between a previous and a newly designed cutter heads, the results shows digitally that the new one is more practicable than the previous one.