Thermophysical and Mechanical Properties of Fiber‐reinforced Composite Material Subjected to High Temperatures

Abstract

Abstract. The bulk density, open porosity, matrix density, tensile strength, bending strength, thermal diffusivity, specific heat capacity, thermal conductivity and linear thermal expansion coefficient of high-density glass fiber reinforced cement composite are determined as functions of temperature up to 1000 °C. The basic physical parameters and mechanical parameters are found to exhibit the most important changes between the reference state and 600 °C pre-heating where the increase of porosity is as high as 40% and both the tensile strength and bending strength decrease to about one third of their original values. The measured dependences of thermal diffusivity and thermal conductivity on temperature indicate that the heat transfer in the studied material is accelerated once temperature achieves 500-600 °C but the change in heat storage expressed by the specific heat capacity is less important. The linear thermal expansion coefficient is not found to be affected by high temperatures in a negative way; it is either lower or comparable to its low-temperature values.

Physical and Mechanical Properties of Composites Made with Aluminous Cement and Basalt Fibers Developed for High Temperature Application

“…Ratio of aggregate in traditional structural concrete is about 85% of concrete volume [6]. Refractory composites are usually formulated as fine grain concrete mixtures with relatively high dose of aluminous cement which is necessary assumption of good resistance to high temperature [7]. Common dose of aluminous cement for refractory composites is about 30% in volume which well document their economical and energy consumption.…”

Laboratory Study on the Influence of Casting on Properties of Ultra-High Performance Fibre Reinforced Concrete (Uhpfrc) Specimens

“…These results are more detrimental than other studies conducted previously on the tensile strength of heat-treated UHPFRC specimens. For example, in the study by Vejmelková et al (2010) it was found that high-density glass fibre reinforced cement composite delivers 33% of its nominal tensile strength after heating specimens to 600 ºC [1112 ºF]. The results presented herein suggest that this UHPCFR delivers on average only 36% of its nominal tensile fracture strength after extreme heating treatment.…”

“…Studies on fibre addition showed a significant improvement in flexural tensile strength of concrete as well as post-peak tensile softening (ductility) (Barris et al 2012). Other studies investigated the effect of different fibre properties -fibre content, length, material types, spatial orientation, and shape -on concrete performance (Kang et al 2011;Downloaded by [Florida Atlantic University] at 19:10 16 November 2014 Vejmelková et al 2010;Kim et al 2011;Hassan et al 2012;Grinys et al 2013;Pajak et al 2013). The results of these studies have shown that flexural tensile strength of UHPFRC increases linearly with respect to the fibre volume ratio from 0% to 5%, and that strength parameters are also linearly dependent on fibre content (Kang et al 2011).…”

The high temperature resistance of a para-aramid fibre-reinforced concrete composite

“…It was proved that utilization of reinforcement should improve not only tensile strength but also other mechanical properties, its durability, fire resistance, etc. Nowadays, the most usual reinforcement is not just a steel bar, but an application of various kinds of fibres becomes common, such as steel fibres [1], carbon fibres [2], glass fibres [3], or organic fibres. The development of polymers fibres represents another possibility of concrete reinforcement.…”

“…This matrix, in the main part of this study, should have been upgraded. Since it was proved in previous studies [2,3,5] that fibres can improve thermal resistance, and para-aramid fibres seem to be suitable reinforcing materials (thanks to their adequate properties [7]), the matrix was reinforced by para-aramid fibres. So the main part of this study deals with residual properties of a para-aramid composite material based on cement compared to the same composite material with no reinforcement.…”