Experimental study on energy saving and thermal insulation of AAC walls and sandwich structures

Abstract

Autoclaved aerated concrete (AAC) materials are increasingly being recognized as an effective method of improving the thermal efficiency of buildings. This paper uses a bolted AAC sandwich wall with rock wool to measure the indoor temperature enhancement and energy savings achieved by applying AAC and autoclaved aerated concrete sandwich (AACS) to building surfaces without ventilation. In addition, the energy efficiency and insulation of sintered brick (S) walls, AAC walls, and AACS walls in three test rooms are discussed in the fall and winter seasons. The study showed that the average daytime room temperatures of the AAC and AACS walls were reduced by 9.11 % and 14.31 %, and the heat load levelling was reduced by 28.41 % and 46.76 % compared to the S walls. The study concluded that compared to the S wall, AAC and AACS walls were reduced by 0.64 W and 0.8 W, respectively, and CO 2 emissions were reduced by 11.78 g/m 2 day and 14.69 g/m 2 day.Under the premise that the building life cycle is 50 years, the energy consumption of the building electricity bill is saved by 157.14 RMB/m 2 and 195.84 RMB/m 2 for AAC wall and AACS wall, respectively, compared with S wall. Therefore, AAC shows a growing trend in the building material market due to its low-carbon insulation, green energy saving, and policy support, and it should be promoted in the construction industry. • A novel AAC sandwich wall combining AAC with rock wool was introduced. • The scaled-down modeling was experimentally investigated to explore the energy efficiency and thermal insulation benefits. • Heat load levels, heat gains, CO 2 emissions, and electricity savings for S walls, AAC walls, and AACS walls were analyzed and calculated.