Property analysis and mixture design of high ductility cementitious composites with totally recycled fine aggregate based on target strength and strain capacity

The natural fine aggregate was completely substituted by the crushed waste concrete particles with original particle grade in preparing high ductility cementitious composite to promote the waste recycling, reduce the environmental pollution, realize the cleaner production and achieve the better properties in this study. The compressive and uniaxial tensile tests were conducted to analyze the effects of water-binder ratio, fiber volume fraction, recycled fine aggregate-binder ratio and fly ash content on the mechanical properties of high ductility cementitious composites with totally recycled fine aggregate (R-HDCC). The test results showed that the compressive strength of R-HDCC decreased significantly with the increasing of water-binder ratio. The peak tensile stress of R-HDCC was improved remarkably as fiber volume fraction increased and water-binder ratio decreased. The ultimate tensile strain of R-HDCC increased significantly with the increasing of water-binder ratio, fiber volume fraction and fly ash content, whereas reduced with the increasing of recycled fine aggregate-binder ratio. The relationships between the compressive strength, the peak tensile stress, ultimate tensile strain of R-HDCC and corresponding key parameters were set up according to the statistical analysis of test results. Then a mixture design method of R-HDCC based on the target strength and strain capacity was further developed. The detailed procedure of using the proposed mixture design method was illustrated with examples, and the reliability of the method was verified by the experimental results in this study and relevant literatures.