Effects of Atmospheric Pressure on Developmental Characteristics and the Stability of Air Entraining Agent for Concrete

In order to ascertain the effects of atmospheric pressure on developmental characteristics and the stability of AEA (air-entraining agent) solution bubbles, AEA solution experiments and AEA solution bubble experiments were, respectively, conducted in Peking (50 m, 101.2 kPa) and Lhasa (3,650 m, 63.1 kPa). Surface tensions and inflection-point concentrations were tested based on AEA solutions, whilst developmental characteristics, thicknesses and elastic coefficients of liquid films were tested based on air bubbles of AEA solutions. The study involved three types of AEAs, which were TM-O, 226A, and 226S. The experimental results show that initial sizes of TM-O, 226A, and 226S are, respectively, increased by 43.5