Behavior of self-compacting fiber reinforced concrete containing cement kiln dust

Self-Compacting-Concrete, SCC containing Cement-Kiln-Dust, CKD may offer several environmental, economic and technical benefits. The use of fibers extends its possibilities since fibers arrest cracks and retard their propagation. An investigation was performed to examine the effect of reinforcing SCC with Polypropylene fiber, PPF, on its stress strain characteristics as well as fresh and mechanical properties. Six mixtures with water-binder ratio (w/b) of 0.45 were conducted. The variables were fiber content, Cf and fiber length, Lf. Lf of 20, 40 and 60 mm and Cf of 0.005, 0.010, and 0.015 kN/m3 were examined. Slump flow and L-box were performed to assess PPF influence on workability. A comparison was carried out among the behavior of SCFRC mixtures in terms of fc, fc-development, tensile strength and shrinkage. It was found that SCC-shrinkage was reduced using PPF and fc of SCFRC was significantly affected by Cf and Lf. The higher the Cf, the higher the obtained fc and improved by 15.3-25.6% using various Cf. Strength development C28/C7 decreased from 1.29 to 1.14, 1.09, and 1.12 using PPF of 0.005, 0.010, and 0.015 kN/m3. PPF and CKD could be successfully used in SCC production in spite of its slightly negative effect on workability and a higher dosage of superplasticizer is required to achieve similar flow properties. The results show that shrinkage of SCC was reduced due to PPF inclusion.