Failure behavior and reinforcing design of degraded tunnel linings based on the three-dimensional numerical evaluation

Void diseases behind the lining can commonly occur in tunnel structures. In this research, failure behavior and reinforcing design of degraded linings with double void were investigated. The effect disease on three-dimensional distribution inner force was explored. Subsequently, stress plastic studied. Then, fiber-reinforced (FRP)-polymer cement mortar (PCM) method concerned. Finally, potential cracking zone discussed. main results research indicated that bending moment is greatly affected by voids lining, exhibits obvious outwards phenomenon within void-affected zone. Concerning characteristics between voids, shear prone to at outer surface, but tensile-shear likely generate surface. addition, rate be significantly spatial voids. Furthermore, FRP-PCM reduce linings. Moreover, including tensile (TCZ), (SCZ), (TSCZ) determined.