Effect of Metakaolin on Concrete Produced with a Pozzolan

The physical and mechanical properties of Portland Cement containing metakaolin or combination of metakaolin and pozzolan ((Palm Bunch Ash (PBA)) and the compatibility between such materials were investigated in this study.  A mix proportion of 1:2:6:4.1 with water/cement ratio of 0.4 were used.  The percentage replacement of ordinary Portland Cement (OPC) with a pozzolan (Palm Bunch Ash) (PBA) and Pozzolan/metakaolin used were 0%, 5%, 10%, 20%, 30% and 40%.  Concrete cubes were cast and cured at different days. Similarly, the setting time was also determined.  At the end of each hydration period, the concrete cubes were crushed and their compressive strength determined.  Similarly the setting time of Ordinary Portland Pozzolan and Ordinary Portland Cement/Pozzolan and Metakaolin was also determined.  The result of the compressive strength of 5-40% replacement cement with the Pozzolan (PBA) ranges from 5.87 – 35.50 N/mm 2 as against 14.10 – 36.22N/mm 2 for the control test. Similarly, the result of the compressive strength of 5-40% replacement of cement with pozzolan and metakaolin ranges from 6.40 – 35.90N/mm 2 as against 14.10 – 36.22N/mm 2 for the control test. The setting time of cement with 5-40% replacement of cement with pozzolan (PBA) ranges from 57 – 109 mins for the initial setting time and 608 – 731mins for the final setting time as against 50 mins and 585 mins respectively for the initial and final setting time of the control test.  Similarly, the setting time of cement with 5-40% replacement of cement with the pozzolan (PBA) and metakaolin ranges from 54-98 mins for the initial setting time and 590 – 692 mins for the final setting time as against 50mins and 585 mins respectively for the initial and final setting time of the control tests.