Sustainable rubberized concrete mixed with surface treated PCM lightweight aggregates subjected to high temperature cycle

Abstract

Porous aggregate can be used as a medium to carry phase change material (PCM) into cement materials. The benefits of using PCM aggregates (PCMA) include the ability to incorporate large amount of PCM (up to about 8% by weight of concrete) into concrete without compromising the mechanical properties. However, an important drawback is the leakage of PCM with time. In this study, the activated silica fume (ASF) is introduced as a surface coating material using a tumbling machine. The experimental series included the investigation on properties of PCMA and PCMA coated with ASF (ASF-PCMA) before and after being subjected to a number of heat/cool cycles, and the properties of rubberized concrete (RC) mixed with PCMA and ASF-PCMA. Results showed that the ASF coating was able to reduce the amount of PCM leakage by about 5.4 times after being subjected to 100 heat/cool cycles. The mechanical properties of RC mixed with ASF-PCMA was slightly better than those mixed with PCMA. For the thermal conductivity (K), ASF coating provides both positive and negative effects to the thermal conductivity of RC depending on the state of PCM that K was being measured. Because of less leakage, the loss in latent heat storage capacity of RC mixed with ASF-PCMA was less than those mixed with PCMA.