Understanding the adsorption of air entraining agents on portlandite: A combined DFT and molecular dynamics investigation

•Adsorption of AEA at portlandite-water interface investigated by DFT and MD simulation.•Adsorption interaction is determined by the electrostatic interaction.•Orientation reversal and a bilayer structure of SDS tend to form.•Strong interaction between water and portlandite cause the competitive adsorption between AEA and water molecules.