Physical and Thermal Properties of Concrete Subjected to High Temperature

Abstract

The physical and thermal properties of concrete under high temperature are obtained in order to provide reference data for material models necessary to evaluate the structural integrity of steel plate concrete containment vessels (SCCV) under accident conditions. Various parameters, such as temperature, heating duration, temperature history (heating, cooling, and the post-cooling process), water binder ratio, cement type, and aggregate type, are considered. Data on the temperature dependence of physical properties (compressive strength, elastic modulus, strain at compressive strength, splitting tensile strength) and thermal properties (thermal expansion strain, specific heat, thermal conductivity) are obtained from concrete of the same mix proportion. The effects of the variables on the properties of concrete are clarified, and the differences between test results and existing codes, such as the Eurocode, are highlighted.

Research on the Thermal Properties of Fireplace Concrete Materials Containing Various Mineral Aggregates Enriched by Organic and Inorganic Fibers

“…4 was 1.50 g/cm 3 , while that of sample no. 5 was 2.16 g/cm 3 . The values of their thermal parameters (thermal power, thermal volume capacity, and thermal energy), however, were found to be similar.…”

“…Samples for mechanical strength testing were prepared in accordance with PN-EN 206 + A1:2016-12 [34], and bending strength measurement was performed after 1, 7, and 28 days of maturation. These measurements used bars with rectangular cross-sections and dimensions of 40 × 40 × 160 mm 3 . The mechanical strength of the tested fireplace materials was determined using the three-point bending method.…”

“…However, there are few publications on the heat-accumulation properties of concrete elements used in fireplaces. Usually, the attention is focused on the role of the thermal conductivity coefficient in the insulation of buildings, and information can also be found on the behavior of concrete at high temperatures above 500 °C, for which the strong influence of the aggregates used and effective reinforcement with steel and polypropylene fibers are highlighted [ 3 ]. The type of aggregate is also important in concretes operating at increased temperatures.…”

“…It follows that different building and mineral materials have different capacities to store energy, the value of which determines if the material is a good heat accumulator and can be used as such in space-heating systems. An important element for thermal properties is the use of natural [ 3 ], light [ 12 , 13 ], hybrid [ 14 ], or recycled [ 15 , 16 ] aggregates. The properties of concrete materials with rubber waste particles were also studied [ 17 ].…”

Concreto em altas temperaturas: um estudo de caso sobre um incêndio em edifício residencial em Minas Gerais

“…Conforme Kakae et al (2017), normalmente o agregado constitui uma parte importante da mistura que compõe o concreto e possui uma primordial influência nas tensões térmicas que provocam sua expansão. Rochas diferentes apresentam diferentes níveis de expansão, mas a mesma rocha nem sempre apresenta os mesmos valores.…”