Effect of Recycled Aggregate Concrete and Steel Fibers on the Fresh Properties of Self-Compacting Concrete

Globally, the amount of solid waste is constantly increasing, and its disposal is one of the critical issues in recent research studies. Concrete waste includes the rubble of demolished buildings, whether old buildings or those that have been subjected to earthquakes, etc. This research project aims to improve sustainability in the construction industry by recycling and reusing coarse aggregate that was previously used in concrete buildings. The objective is to utilize this recycled material to produce self-compacting concrete (SCC) and assess its performance in its fresh state. By finding new ways to repurpose materials that would otherwise go to waste, this research contributes to developing environmentally friendly practices and reducing the industry's carbon footprint. Furthermore, evaluating the performance of the recycled coarse aggregate in SCC will provide insights into its potential for future use in construction projects, which could ultimately lead to cost savings and improved efficiency in the industry. Recycled coarse aggregate (RCA) was used as a substitute for the natural coarse aggregate (NCA) with volume ratios of 0, 25, 50, 75, and 100%, and steel fibers (SF) were added to the concrete with different volumes ratios (0, 0.5, and 1 %). Workability tests such as slump flow, V-funnel, and L-box tests were carried out for the mixtures in their fresh state. In general, the results of the experimental work showed that the fresh properties indicated that almost all SCC mixtures were within the specified range, as stated in EFNARC requirements