Fig. 1. Network structure of Mask RCNN

Fig. 2. Network structure of improved FPN

Fig. 3. Structure diagram of SEM module

Fig. 4. Add feature fusion

Fig. 5. Category classification diagram of crack diseases

Fig. 6. Data set annotation visualization

Fig. 7. Loss curves

Fig. 8. Performance comparison diagram of each network model

Fig. 9. Detection results of fine cracks

Fig. 10. Detection results of larger cracks

Fig. 11. Detection results of complex cracks