Extremely-ductile alkali-activated slag-based composite with a tensile strain capacity up to 22%

Highly-ductile alkali-activated slag-based composites (HD-AASC) are fiber-reinforced cement-free materials possessing pseudo strain-hardening behavior and multiple-cracking phenomena. In this research, the feasibility of developing extremely-ductile alkali-activated slag-based composite (ED-AASC) with a tensile strain capacity over 20% is presented. Specimens with a moderate amount of sand and crumb rubber particles were made by applying new mixing and curing procedures. Then the density, compressive strength, and tension tests were performed. Test results showed that the ED-AASC (R5-S8-M1 mixture) had a tensile strain capacity of 22.3%, compressive strength of 53.6 MPa, and average crack width of 212 mu m. By adopting two performance indexes (fc epsilon ts and fts epsilon ts), the performance of ED-AASC was compared with those of previous high-ductile composites; the tensile strain capacity of the composite was also compared with the minimum extensibility of steel bars for concrete reinforcement, as specified in ASTM and ISO. In addition, the sustainability of ED-AASC was evaluated.