The study aims to explore the effects of crimped polypropylene fiber (PP) inclusions in slag (GGBS) based concrete, which was used as cement replacement. The mode of accelerated curing on mechanical properties of the GGBS based concrete for various mixes of concrete was investigated systematically. The addition of PP fiber in the concrete increases the strain hardening properties of the concrete due to matrix reinforcing efficiency offered by discrete fibers present in the matrix. The experimental test results showed an increase in bending stress in concrete with an increase in percentage of PP fibers from 0.1% to 0.3% Vfof concrete. In the case of slag concrete, the optimum addition of slag up to 25% proved to be effective in improving the concrete strength properties. Further replacement of OPC in GGBS up to 50% concrete mixes showed a reduction in the compressive strength in normal curing. Indeed, an apparent increase in the compressive and flexural strength of slag based concrete was noticed in accelerated curing for various mixes of structural concrete.