Effects of hybrid steel fiber reinforced composites on structural performance of segmental linings subjected to TBM jacks

摘要

In recent years, incorporating fibers as the main reinforcement in segmental lined tunnels has gained significant interest. Damage to segmental linings due to the thrust force of TBM jacks is one of the main problems that arises in the assembly phase, reducing serviceability and durability of tunnels. The aim of this paper is to experimentally and numerically investigate the effects of fiber size, content, and hybridization on the performance of steel fiber reinforced concrete (SFRC) tunnel segments under TBM jack forces compared to conventionally reinforced concrete (RC) segments. In this regard, different scenarios of segment support conditions and eccentricity of the applied TBM jack loads are investigated in a particular real tunnel. The results showed that under various configurations of segment support and load eccentricity, SFRC composites show better performance over RC in both SLS and ULS conditions under TBM jack loads in terms of cracking strength and damage propagation.