Analysis of the effect of replacing steel fibers with bars in reinforced concrete tunneling segments by DBA method

Application of the concrete segments used in tunneling always lead to extensive cracks due to the impact of trust jack or forces created in the transportation stage. On the other hand, use of fiber reinforced concrete is of great interest because of reducing labor costs. Inclusion of fibers in concrete segments improves the mechanical properties and results in resisting high tensile stress. The purpose of this investigation is analysis of the replacement effect of steel fibers with bars in reinforced concrete segments applied in tunneling by using DBA method. Firstly, requirements and standards of fiber reinforced concrete segments were studied. Then, reinforced concrete segments simulated by ABAQUS finite element software were loaded. One of the reinforced concrete segments included reinforced concrete segment with steel bars. Also, to evaluate the replacement effect of steel fibers with bars, two steel fiber reinforced concrete segments with 0.5 and 1.0 percentage of volume content were simulated. Finally, the results obtained from DBA method considering compressive, tensile, and flexural capacity and cost showed that the reinforced concrete segment with 1.0% volume content of steel fiber was the most optimal among all reinforced concrete segments.