Experimental investigation of the effect of salt on the hygroscopic properties of autoclaved aerated concrete

作者：He, Jian; Li, Qiong^*; Meng, Qinglin; Ren, Peng; Li, Shan; Wu, Haotian

来源：CONSTRUCTION AND BUILDING MATERIALS, 2023, 370: 130412.

DOI：10.1016/j.conbuildmat.2023.130412

• Porous building materials
• Salt
• Hygroscopic properties
• Equilibrium moisture content
• Sorption isotherm

The hygroscopic properties of autoclaved aerated concrete (AAC) significantly affect building energy consumption. However, the impact of salt on the hygroscopic properties of AAC in buildings in marine environments has not been sufficiently investigated. Thus, we tested the hygroscopic performance of AAC specimens with different salt contents at various humidity levels. The results show that the equilibrium moisture content (EMC) of the AAC is 0.98-1.25 (0.99-3.68) times higher in the presence of salt than in the absence of salt at low (high) relative humidity (RH) (RH threshold of 75.5%). Furthermore, an equation to predict the EMC of salt-containing materials was proposed based on existing adsorption equations and the results of this study. A comparison with related studies indicates that the reason for the high prediction value of the proposed prediction model may be an insufficient moisture absorption time. The proposed model can be used to calculate the EMC of building materials with different salt contents.