Case Studies in Construction Materials (Dec 2023)
A new heat resistant load bearing system incorporating honeycomb structured cementitious composite investigated via experiments and modelling
Abstract
The load-bearing cementitious materials such as concrete rely on passive insulation to resist heat in fire and other high-temperature events. This study introduces a novel load-bearing system, incorporating a honeycomb-structured cementitious composite (HSCC) to enable adjustable active heat dissipation. Compared with passive thermal insulation, active heat dissipation brings substantial improvement on heat resistance performance under compressive load. The study investigated the heat transfer process of the HSCC material fabricated by 3D-printed micro scaffolds by combining the microscopic thermal imaging method and finite element simulation. The proposed material has a conductivity of up to 0.24 W/mK, which shows a 30% improvement in heat resistance compared to lightweight concretes. The total compressive strength reduction is ten times less than ordinary concrete under elevated temperatures at 1300 °C. The microscopic thermal imaging provided experimental data to enable the development of multi-phase simulation models, which allowed further predictions of the material performance under elevated temperatures. The novel load-bearing system enabled ventilation through the HSCC in combination with the low thermal conductivity of the HSCC, which allowed this novel system to demonstrate a capacity loss at 1300 °C that was ten times less than that of ordinary concrete walls. Furthermore, the effect of ventilation and heterogeneity in the HSCC on the heat dissipation and temperature distribution in the materials is also characterized by this study.
