Study on the influence of ground characteristics on wearing of shield machine cutter bit in gravel ground

Infrastructure development in urban areas has progressed rapidly, and the demand for construction of pipes for electricity, gas, water supply and sewerage, etc. is increasing. In the urban construction of pipe, the non-open cut method is generally used to prevent traffic disturbance, building influence, noise and vibration, one of which is a Shield method. Shield method is a construction method that rotates the cutter head at the tip of the shield machine, excavates the ground, and constructs an underground pipe ditch. In recent years, construction condition of Shield method is diversified such as long distance, great depth, high water pressure and gravel ground, etc. Bit wear is a factor affecting workability and economic efficiency in Shield method, and the various investigations have been discussed so far, but the quantitative guidelines on bit wear prediction have not been established because the wear factor is complicated in the gravel ground. This study was conducted in order to obtain fundamental knowledge for predicting bit wear in gravel ground.