Mechanical properties of self-compacting lightweight ‎concrete containing pumice and metakaolin

Abstract

Self-compacting lightweight concrete (SCLC) is a novel ‎type of concrete that combines the benefits of the ‎lightweight and self-compacting concrete (SCC) types. In ‎this research, the optimal amount of metakaolin used in ‎lightweight concrete containing pumice has been ‎obtained based on the best concrete performance in ‎terms of the greatest simultaneous increase in ‎compressive, tensile and flexural strengths. After ‎choosing the SCLC mixing scheme, L-Box, V-Funnel, ‎Slump flow, and T50 tests were performed to investigate ‎the flowability, passing ability, viscosity, and concrete ‎resistance against segregation. Then, the mechanical ‎properties of SCLC have tested by replacing metakaolin ‎with 0, 5, 10, 15, and 20% by weight of cement.‎‏ ‏The ‎research results have demonstrated that metakaolin ‎enhances ‎the mechanical strength of SCLC. In addition, ‎by adding metakaolin in the amount of 15% cement ‎weight, the process of improving concrete strength ‎continues. The 28-day SCLC specimens containing 15% ‎metakaolin had compressive, splitting tensile and flexural ‎strength of 26%, 14%, and 11% higher than those of ‎SCLC without metakaolin, respectively.‎‏ ‏‎ Furthermore, ‎formulas that can ‎predict compressive strength, tensile ‎strength, and ‎flexural strength of 28-day SCLC ‎‎containing ‎metakaolin have been presented.‎

Keywords

• metakaolin
• ‎ mechanical properties
• ‎ taftan pumice
• ‎ self-compacting
• ‎ lightweight concrete.‎