Influence of Defoamer on the Properties and Pore Structure of Cementitious Grout for Rebar Sleeve Splicing

Grout sleeve splicing of rebar is a major technology in prefabricated buildings, and cementitious grout for (hereinafter called grout) an essential material this technology. Grout, with its excellent mechanical properties, improves the stability splicing. In study, properties were improved by introducing admixture form defoamer, influence defoamer on fluidity, loss rate wet apparent density strength was investigated. The action regulating pore structure further analyzed using mercury intrusion porosimetry (MIP) method. results showed that when dosage increased from 0 to 0.025%, fluidity initially then decreased, but there no change at 30 min. continuously, whereas flexural compressive generally tended stabilize. MIP test volume range 6 nm decreased 60 μm. However, μm 300 size range, 0.0025% 0.0075%, 0.005% 0.001%. porosity slightly as 0.01%. introduction can optimize improve properties. systemically studied view providing technical theoretical guidance sleeve-splicing construction.