Characteristics of Ultra-High-Strength Self-Compacting Concrete (UHSSCC) Containing Macro Steel, Polypropylene Fibers and Local Materials

: Self-Compacted Concrete (SCC) structure has been widely utilized in high-rise buildings and long-span structures owning to the advantages of high bearing capacity, good seismic performance, and superior corrosion resistance. The current investigation is aimed at developing strengths of (SCC) to more than M 120 Grade with keeping its requirements of workability such as flowability, passing ability and segregation resistance. These properties have been examined by using slump flow, L-box, V-funnel respectively. This study includes achieving acceptable grade of concrete by finding the ultimate mechanical strengths and fresh properties of self-compacted concrete by using locally materials and available in local markets. Also, Ultrasonic Pulse Velocity (UPV) test and sorptivity test were performed. To achieve the purpose, 12 mixes were performed and divided to groups. Group (1) only fine aggregate is used. Group (2), quartz powder (QP) was used as a filler material by 26% replacement from sand. Each group include, Silica Fume (SF) and Metakaolin (MK) as a pozzolanic replacement material by percentages (SF/MK) (22% - 0% and 11% - 11%) respectively. In addition to two types of fiber were used (steel and polypropylene fiber) by (0-160) kg/m3 and (0-1.8) kg/m3 respectively as reinforcing materials The results indicate that local material can produce ultra-high strength self-compacted concrete more than 120 Mpa. Steel fiber and polypropylene fibers improved compressive, tensile and flexural strength. Using polypropylene fiber decrease sorptivity coefficient due to high amount of porosity. This result shows significant reduction in capillary porosity and inner conductivity of pores by using fibers.