Behaviour of limecrete under fire conditions

Hydraulic lime concrete (limecrete) is a material that has a lower environmental impact than that of ordinary Portland cement (OPC) concrete and, consequently, may be increasingly used in some construction applications. Because of its reduced strength, pozzolanic materials, such as metakaolin, are commonly used to improve its strength and durability. Simultaneously, to the increased interest in more sustainable materials, the fire behaviour of materials has also deserved an increased attention during the last years because of some important disasters that occurred. In this study, the fire behaviour of limecrete has been investigated. To increase limecrete performance, hydraulic lime has been replaced by metakaolin in different percentages. Fire tests at different temperatures (200, 400, 600 and 830 degrees C) and different durations (30 and 60min) have been performed and the residual strength and chemical changes using X-ray powder diffraction and thermogravimetric analysis techniques were investigated. It became apparent that a 20% replacement of hydraulic lime by metakaolin leads to an improved performance at room temperature and fire loading. Copyright (c) 2011 John Wiley & Sons, Ltd.