Effect of silica fume and coarse aggregates on fire resistance of high performance concrete

• Main Author: Ng, Jacob Jin Hao
• Other Authors: Tan Kang Hai
• Format: Final Year Project
• Language: English
• Published: 2016
• Subjects: DRNTU::Engineering::Civil engineering::Construction technology
• Online Access: http://hdl.handle.net/10356/67935
• Institution: Nanyang Technological University

For most construction projects around the world, concrete had been the most frequently used element. The use of concrete ranges from the pile caps to the roofs to the building. Recently, use of normal strength concrete was gradually replaced by the use of high strength concrete. However, the dense and compact structure of high strength concrete would lead to the phenomenon termed as explosive spalling. Spalling had occurred due to the thermal stress and pore pressure induced stresses which led to the insufficiency of porosity and connectivity to evacuate the built up pore pressure that were created during the exposure to high temperature. The mechanisms of spalling and different factors contributing to explosive spalling will be discussed in literature review. The mechanisms include thermal stress, pore pressure induced stress and the combination of these two mechanisms. Factors that influence the extent of spalling include the effects of silica fume and coarse aggregates would be investigated and discussed in the report. For this project, the experiments were carried out in three different stages, namely, mechanical properties, permeability at high temperature as well as spalling tests. Mechanical properties include compressive and uniaxial tensile strength tests, hot permeability test from ambient temperature to 300°C and spalling test under ISO-834 heating curve for 1h. In all these stages, the effects of silica fume and coarser aggregates will be investigated. In all the experiments, 3 mixes would be carried out and evaluated. Strengths and permeability of the concrete recorded would be used to analyse the effect of silica fume and coarse aggregates on explosive spalling.