Development of a soil abrasion test and analysis of impact of soil conditioning on tool wear for soft ground mechanized tunneling using EPB machines

a (*),Omid Forough(**), Cristina Gabriela Onate Salazar(*) (*) Politecnico di Torino (Italy), colorado school of mines (USA) A. B. Unknown Affiliation, City, Country. In the recent years, Earth Pressure Balance (EPB) shields have been successfully used in many tunnels in urban areas. One of the critical issues for successful EPB tunneling is the use of proper soil conditioning to reduce wear and torque. Among the parameters that can affect tool wear, soil conditioning is the most important one that can be controlled by the operators. Soil conditioning has been used to improve the performance of tunneling machines and to expand their area of application and is mostly done by adding various foaming agent. To assess the impact of the soil conditioning on tool wear, specific laboratory scale test was developed. Review of the initial test results shows that with using soil conditioning, the wear of tool can reduce. The results also show that agents can be designed to offer optimum performance for a target ambient pressure.