Finite Element Method for Prediction of Rock Breaking Performance of the Tipped Hob With Different Tooth Profiles

Xiukun Hu,Hongxiang Jiang,Changlong Du

doi:10.1109/access.2020.2980427

Abstract

The raise boring machine, which plays a crucial role in wellbore construction, has been widely applied in subway tunnels and mine construction projects. High levels of quality and safety, make it recognized and promoted by an increasing number of users. The tipped hob as a rock-breaking cutter of the raise boring machine poses a direct influence on the efficiency of the well-bore construction. In this paper, the finite element software LS-DYNA is employed to establish the model of the crushed rock with the tipped hob, and the accuracy of the model is examined by experiments. On this basis, the variation laws and correlations of feed force, lateral force and positive force under different penetration depths are studied. The results show that as the penetration depth increases, the feed force, lateral force and positive force all grow exponentially. In the geological environment with high rock hardness, spherical tooth can effectively reduce cutter wear and conical tooth can achieve higher crushing ability. The research results provide a theoretical basis for the selection of a suitable tipped hob to improve rock breaking efficiency.

Highlights

In mining development, hydropower and other underground construction projects, shafts or inclined shafts are often used in import and export communication channels and ventilation
Compared with other construction methods, raise boring machine (RBM) has been widely applied in major engineering construction projects because of its obvious advantages in safety, construction speed and engineering quality
Wu et al [31] using a coupled finite element method (FEM)-discrete element method (DEM) method successfully applied to simulate the rock failure process caused by a TBM cutter under different confining pressures

Summary

INTRODUCTION

Hydropower and other underground construction projects, shafts or inclined shafts are often used in import and export communication channels and ventilation. X. Hu et al.: FEM for Prediction of Rock Breaking Performance of the Tipped Hob With Different Tooth Profiles the specific energy of the relevant cutting parameters. Li and Shi [18] proposed a dynamic material model for expressing the mechanical behavior of a rock material under high confining pressure and high strain rate It was simulated and analyzed by finite element software LS-DYNA, and successfully described the brittle tensile damage and plastic compression damage of rock materials. Wu et al [31] using a coupled FEM-DEM method successfully applied to simulate the rock failure process caused by a TBM cutter under different confining pressures. The finite element software is utilized to analyze the force during rock-breaking process, and the influence of different tooth profile on rock fragmentation is explored. The rock-breaking theory of the hob provides a solution to the selection of a tipped hob, helping to achieve low energy consumption and high efficiency in different geological environments

MODELS AND METHODS

RESULTS AND DISCUSSION

DATA EXTRACTION

CONCLUSION