To investigate the interaction between shield cutter and concrete

laboratory cutting experiments were carried out

which verified that the essence of cutting is the cyclic process of collision

extrusion

cutting

and peeling between cutter and specimen. The influence of tool rake and clearance angles

tool shape

cutting depth

and specimen strength on the normal cutting force Fn and tangential cutting force Ft of the tool was obtained through the cutting force testing system

and the fluctuation range of Fn

Ft and cutting force Fc under the influence of each factor was obtained through analysis. The research shows that the essence of cutting concrete with cutters was the repeated cycle of collision

cutting

and peeling

and the cutting force was always in a fluctuating state. The rake face played a major role in the rock breaking task

and the required Fn and Ft and their fluctuation decreased with the increase of the rake angle. The cutter with larger rake angle had more obvious pulling and shearing effects on the concrete. The mean value of Fn and Ft had a linear relationship with specimen strength and cutting depth. The larger the specimen strength and cutting depth were

the larger Fn and Ft were

and the smaller the fluctuation in its direction was. The effect of cutting depth on the fluctuation of Fc was greater than that of the specimen strength. The particle size of the debris increased with increasing cutting depth

while the debris at cutter tip was in powder form.