Static and dynamic behavior of cemented heat storage materials

Abstract

Assessing the mechanical and thermal stability of heat storage media is vital in the design and wellbeing of sensible heat storage systems, which are typically designed below ground level or as part of the sub-structure of buildings with load bearing capabilities. Nevertheless, considering the importance that a mechanically sound heat storage media (especially at elevated temperatures) has on the efficiency and performance of heat storage systems, it has not been given adequate attention in past studies. On this basis, the mechanical performance of two commercial cemented heat storage materials at different curing periods, pressure and temperature is studied in this research. The influence of curing period on the mechanical strength of the materials was studied by performing unconfined compression tests, where as to study the effects of pressure and temperature on seismic velocities, and hence mechanical properties of the materials, laboratory tests on P- and S-wave velocities were performed. Ultrasonic wave velocity studies can be used to estimate many geomechanical properties of materials such as density, elastic modulus, Poisson’s ratio etc., thus providing an accurate and reliable estimate of the mechanical properties of rocks and cemented materials. The results presented in this study show a considerable dependence of the mechanical behavior of the investigated materials on curing period, pressure and temperature, which when unaccounted for can result in the inaccurate planning and design of heat storage systems.