ABSTRACT
This research is an investigation into the effects of pulverized burnt brick on selected cement brands used in Nigeria. Pulverized burnt brick obtained from grinding Adamawa burnt brick was used, the burnt brick was established to have the highest pozzalinic activity by Sa'ad(2006). The PBB was reactive at w/c = 0.65, 10% replacement of cement by PBB and 1:6 mortar mix ratio. Test such as specific gravity, setting times, soundness test, oxide composition and compressive strength were conducted. PBB gave the lowest specific gravity of 2.68 while for OPC, cement B gave the highest specific gravity of 3.35 and cement A gave the lowest specific gravity of 3.16. The highest and lowest initial setting times for the blended cement pastes were 206 and 118 minutes for cement E and D which was 98.8% and 78% of the control cement pastes respectively. The highest and lowest final setting times for the blended cement pastes were 257 and 162 minutes for cement C and D which was 107% and 66.94% of the control cement pastes respectively. Control cement pastes did not undergo expansion except for cement A and D. The former and latter underwent expansion of 1mm and 0.5mm respectively while for the blended cement pastes all cement brands underwent expansion of 1mm each except cement C which did not undergo expansion. The brands of cement satisfied the oxide composition for cement as stated in ASTM C150 - 07. The highest and lowest composition of SiO2 (A) was 13.2% and 6.3% for cement A and E while for CaO (A) was 82.63% and 71.66% for cement D and A respectively. The highest and lowest composition of Al2O3 (6% max) was 2.6% and 1% for cement A and D while for Fe2O3 (6% max) was 5.79% and 4.52% for cement E and C respectively. At the end of 90 days of curing, blended mortar cubes made with cement C gave the highest compressive strength of 5.03N/mm2 with the PBB followed by cement E with 3.54N/mm2. The former and latter compressive strengths were 106% and 145% of their control mortar cubes. The experiments indicate cement C to be suitable with the PBB.