Estimation Method for TBM Cutterhead Drive Design Based on Full-Scale Tunneling Tests for Application in Utility Tunnels

Abstract

The utility tunnels used for electricity transmission are in high demand these days. The literature presents many limitations in the currently used cutterhead drive design procedure while using a shield tunnel boring machine (TBM) for the excavation of these relatively small diameter tunnels. In order to develop an appropriate design method specially for cutterhead drive, experimental data obtained through the operation of a 3560 mm diameter shield TBM were used in this research work. For experimental purpose, an earth pressure balance (EPB) shield TBM was manufactured and a facility was established for performing the full-scale tunneling tests. Numerous tests were performed through the variation of TBM operational parameters such as thrust force and the rotational speed of the cutterhead at four UCS (Uniaxial compressive strength) levels of artificial rock mass. The relationships between thrust force and torque were mainly established and the effects of UCS and rotational speed of cutterhead on these relationships are analyzed through a representative case of 100 MPa UCS. A novel torque estimation method is also presented in this study which can be conveniently used in the cutterhead drive design while using small diameter shield TBMs.