The Effects of Concrete Temperature on Air Void Parameters in Pumped Concrete

Abstract

This study investigates the effects of concrete pumping on air content, SAM Number, spacing factor, and freeze-thaw performance. This work focuses on how the air dissolves under pressure and then returns to the concrete at room (30°C/86°F), cold (8°C/46°F), and hot (40°C/104°F) temperatures. The research reveals that concrete pumping leads to a significant reduction in air content, with cold mixtures experiencing higher air loss compared to room temperature and hot mixtures. Despite these changes, freeze-thaw performance remains satisfactory for mixtures with initial air content above 4% and SAM Number below 0.32. The study also observes that the dissolved air bubbles return to the concrete with a similar bubble distribution as was in the original mixture.