Abstract: The wear law and life characteristics of disc cutter of shield in waterrich pebble drift ground in Fengwen Section and Mingyi Section of Chengdu Metro Line 17 are studied. Firstly, the wear forms and wear coefficients of cutterhead disc cutter with different opening rates in two sections are compared. And then the life prediction model of disc cutter based on field measured data is used to predict the distance of cutter check and change. Finally, the prediction effect is verified by the secondary of cutter change. The results show that: (1) The wear forms of disc cutter in waterrich pebble drift ground are mainly pointed wear and eccentric wear, and the eccentric wear disc cutter are mainly distributed in the edge and center of cutterhead. (2) The relationship curve between the wear coefficient of disc cutter and the radius of installation position is Ushaped; the wear coefficient of the center disc cutter and the edge disc cutter is larger, while the wear coefficient of the front disc cutter is smaller. (3) The opening rate of cutterhead is an important factor that affects the wear coefficient and eccentric wear probability of disc cutter.

Key words: pebble drift ground, shield disc cutter, wear law, wear coefficient, cutterhead opening rate, life prediction