Impact of lightweight aggregate on concrete thermal properties

摘要

The porous structure of manufactured structural lightweight aggregate (LWA) is responsible for differences in mechanical, durability, and thermal performance of lightweight concrete (LWC) compared to normalweight concrete (NWC). The thermal properties of LWC have not been widely studied, and publications containing values of heat capacity and thermal conductivity for LWC provide few if any details on materials, mixture proportions, and moisture states. In this study, testing was performed to determine the thermal conductivity and heat capacity of sand lightweight concrete (SLWC), alllightweight concrete (ALWC), and NWC mixtures for building and transportation applications, as well as lightweight and normalweight grout mixtures. Results of this study were evaluated then compared to published values to demonstrate the influence of this LWA on properties of the concrete and grout mixtures. Statistical models were developed to demonstrate the influence of expanded slate LWA on the thermal conductivity and heat capacity of the concrete studied.