The research focuses on using recycled materials to improve concrete behavior in less developed countries, addressing inefficiency, access, and costs. Recent research confirms that recycled materials improve concrete behavior, but significant gaps remain in effectively utilizing non-local materials and additives. This study employed controlled laboratory experiments using standardized protocols to evaluate the effects of recycled fibers, glass waste, and additives on concrete; samples included microsilica, metakaolin, nanosilica, and glass fiber. First, a reference sample (without fibers and additives) was prepared and subjected to various experiments. Following testing, the compressive strength, modulus of rupture, and post-cracking load-bearing capacity of the specimens were evaluated. Approximate equations were also presented to estimate the results of compressive strength, modulus of rupture, and load-bearing capacity after cracking, which were in good agreement with experimental results. The addition of 10% and 15% microsilica increased compressive strength by 12% after 7 and 28 days, respectively. Conversely, incorporating 2.5% glass fiber reduced compressive strength by 16.75% and 11.3% in 7-day and 28-day samples, compared to the reference sample. The modulus of rupture was greatly affected by the addition of glass fiber and increased. Furthermore, the load-bearing capacity of the samples increased after cracking with the addition of microsilica