Experimental investigation on effect of ambient pressure of conditioned soil on tool wear in earth pressure balance (EPB) shield tunneling
The use of mechanized excavation especially shielded tunnel boring machines (TBMs), has grown rapidly in various soft ground tunneling projects. One of the advantages of mechanized tunneling compared to conventional method is the ability of the machines in coping with various geological conditions. In the recent years, Earth Pressure Balance (EPB) shields have been successfully used in many tunnels in urban areas while the range of soil types that it can handle has expanded. One of the critical issues for successful EPB tunneling is the use of proper soil conditioning to reduce wear and torque. Estimation and assessment of the effects of abrasive ground on the primary and secondary wear of tools and machine components, costs, and schedule of a project is still a sticking point in many projects.