High Temperature Exposure of HPC – Experimental Analysis of Residual Properties and Thermal Response

Abstract

Abstract. The effect of high temperature exposure on properties of a newly designed High Performance Concrete (HPC) is studied in the paper. The HPC samples are exposed to the temperatures of 200, 400, 600, 800, and 1000°C respectively. Among the basic physical properties, bulk density, matrix density and total open porosity are measured. The mechanical resistivity against disruptive temperature action is characterised by compressive strength, flexural strength and dynamic modulus of elasticity. To study the chemical and physical processes in HPC during its hightemperature exposure, Simultaneous Thermal Analysis (STA) is performed. Linear thermal expansion coefficient is determined as function of temperature using thermodilatometry (TDA). In order to describe the changes in microstructure of HPC induced by high temperature loading, MIP measurement of pore size distribution is done. Increase of the total open porosity and connected decrease of the mechanical parameters for temperatures higher than 200 °C were identified.

Effect of the curing process on the thermomechanical properties of calcium aluminate cement paste under thermal cycling at high temperatures for thermal energy storage applications

“…Previous experimental research showed how curing temperature could affect the rate and degree of conversion of CAC conversion in terms of gibbsite (AH 3 ) formation [15]. The influence of curing temperature conditions in calcium aluminate cement highly affects the physic-mechanical outcomes and the reactivity of the cement [20]. Below a water/cement ratio of 0.40, calcium aluminate cement is not entirely hydrated; consequently, when the conversion occurs, the water release allows further hydration of the paste, filling all the pores.…”