Based on theoretical analysis of specific power of broken hard rock

a mode of specific power of broken hard rock has been established. Tools structural dimensions and rock mechanical performance and broken technique three types parameters

which are interrelated with specific power of broken rock

have been determined. Fuzzy logic method (FLM) has been introduced to predict the specific power of broken rock. Taking the above three types parameters for input variables of FLM and the specific power of broken rock for output variables of FLM

a fuzzy prediction model of the specific power of broken rock has been established. The model is applied to a project instance. The comparison of the project practice real value and the model value shows that the model values are close to the project practice real values. It is indicates that the model is reasonable and fuzzy if-then rules can express the experience of the project practice. Given input variables

the model can predict effectively specific power of broken rock.