Support Boot Mechanisms of Shaft Boring Machine for Underground Vertical Tunnel Construction

Abstract

Shaft boring machines are significant to the mechanized construction of underground vertical tunnels in water conservancy projects, underground mining, transport infrastructure, etc. As one of the main components, the support boot mechanism should apply large pressure on the sidewall to provide enough friction for balancing the gravity and boring torque of the shaft boring machine. In this paper, novel support boot mechanisms are presented to output desired pressure along the radial direction of the cylindrical tunnel, as well as to provide steady support during the vertical tunnel construction. The proposed support boot mechanisms are based on deployable modules with one degree of freedom by converting axial translation into radial one. With this characteristic, synchronous unfolding movements of multiple support boots can be realized. To avoid the failure of the support due to the damage to the tunnel surface, the adjusting modules are adopted at the ends of support boots for changing their radial position. In addition, an adjustment device is presented based on the 3-RPS parallel mechanism to control the direction of the boring head and realize the advancement of the whole shaft boring machine. Combined with the support boot mechanism, the adjustment device, as well as the advancement mechanism, the concept designs of shaft boring machines are presented. This work provides a reference for the structural design and candidates of deployable-module-based support boot mechanisms in shaft boring machines for underground vertical tunnel construction.