The work aimed to utilize ground clay bricks (GCB) in the production self-compacting concrete. Physico-mechanical, rheological and microstructure of cement pastes and concrete were investigated. Total powder contents were 400 kg/m3, the cement was replaced by GCB by 0.0, 50, 100 and 150 kg/m3. The compressive strength of concrete decreased with GCB content in the absence of Self-compacting concrete (SCC), whereas, increases in the presence of SCC up to 28 days. Increase of GCB content up to 250 kg/m3, the compressive strength of concrete increases. GCB enhances the compressive strength due to the pozzolanic reaction to produce additional CSH, which precipitated in some open pores. The compressive strength of OPC pastes increase with SCC up to 1.5 mass%, whereas decreases with SCC up to 2 mass%. On the other hand, pastes made with 12.5 and 37.5% GCB in the expanse of OPC cement show higher compressive strength with SCC at 28-1095 days. The efficiency of SCC decreases as GCB content increases up to 12.5%, whereas the efficiency increases with GCB content up to 37.5%. The presence of SCC superplasticizer, the microstructure displayed a more dense arrangement of microcrystalline C-S-H as the main hydration products with sheets of Ca(OH)2 as shown in the micrograph. Useful conclusions and recommendations concerning use of 30-40 mass% of GCB in self-compacting concrete. |
