Multifunctional Conductive Cementitious Composites Including Phase Change Materials With Snow/Ice Melting Capability

Abstract

In winter, snowfall and icing below 0 °C cause disruption of transportation on roads and airlines, as well as accidents with loss of life and property damage. Within the scope of the mechanical methods (ploughing, sweeping, etc.) applied for cleaning snow and ice, labor, equipment and operator costs affect the resources of our country negatively. On the other hand, the deicing salt method, which is frequently used to melt snow and ice, when applied to asphalt pavements, can cause disintegration, deterioration, and the adherence between aggregates and bituminous mixture significantly weakening and decomposition of aggregates, together with freeze-thaw effects. In addition, freezing and thawing cycles and de-icing salts cause spalling damage on concrete pavements, causing significant damage to the surface of the pavement, and in later stages, the de-icing salt solution leaks into the pavement and causes reinforcement corrosion. In order to eliminate the negative properties of mechanical methods and deicing salts, which are within the scope of traditional applications, Phase Change Materials (PCM), which is a renewable energy source and has the ability to store and release the heat energy of the sun, potential of melting snow and ice in concrete and asphalt road pavements has been started to be investigated in recent years. Within the scope of the thesis, a new approach was exhibited by departing from the previous studies. In the first part of the thesis, cement-based composites with self- levelling properties and sufficient strength were produced. In the second part, multifunctional cement-based composites with increased thermal conductivity were developed by adding conductive materials to this composite produced. In the third part, microencapsulated organic PCM were included in the multifunctional cement-based composites developed. Thus, it is aimed to produce pavements that can melt snow and ice by providing rapid transfer of the heat energy to the surface where the snow/ice is found thanks to the improved thermal conductivity of the composite. In addition, thanks to the improved conductive feature, it is aimed to achieve snow/ice melting performance with a lower amount of PCM compared to the usage rates in the literature. In the last section, studies were carried out to create sufficient bond strength with the substrate concrete and asphalt in order to apply the composite, which has the ability to melt snow/ice on its own, as a pavement on asphalt and concrete roads.