Mechanical, rheological, durability and microstructural properties of high performance self-compacting concrete containing SiO2 micro and nanoparticles

• Published in: Materials in engineering Vol. 34; pp. 389 - 400
• Main Authors: Jalal, Mostafa, Mansouri, Esmaeel, Sharifipour, Mohammad, Pouladkhan, Ali Reza
• Format: Journal Article
• Language: English
• Published: 01.02.2012
• Subjects: Binders; Durability; Microstructure; Nanocomposites; Nanomaterials; Nanostructure; Rheological properties; Scanning electron microscopy; Self-compacting concrete
• ISSN: 0261-3069
• DOI: 10.1016/j.matdes.2011.08.037

The durability and mechanical, rheological, and microstructural properties of high performance self compacting concrete (HPSCC) incorporating SiO2 micro and nanoparticles were investigated. A fraction of Portland cement was replaced by different amounts of microsilica, nanosilica and a blend of micro and nanosilica as 10%, 2% and 10% + 2% respectively. Three different binder contents as 400, 450 and 500 kg/m3 with a constant water to binder ratio (w/b = 0.38) were investigated. The rheological properties were determined through slump flow time and diameter, V-funnel flow time and L-box tests and mechanical characteristics were determined. Durability properties were evaluated by water absorption, capillary absorption, Cl ion percentage and resistivity tests. The microstructure of the concrete was also assessed using SEM. The results showed that the properties improved significantly for the specimens containing micro and nanosilica. Improvement of Cl ion percentage and resistivity results in the micro and nanosilica blended mixtures was also noticeable. The SEM micrographs showed more refined and packed pore structure of the concrete containing admixtures especially at longer ages which could lead to strength enhancement and the durability properties of HPSCC specimens.