引气剂对机制砂海工混凝土抗冻性能的影响

系统研究了不同引气剂掺量及类型对机制砂海工混凝土抗冻性能的影响,并通过气孔间距试验、电镜扫描等试验方法,分析了冻融环境下不同引气剂对机制砂海工混凝土的作用机理。试验结果表明,当ML类引气剂掺量为0.4%时,机制砂海工混凝土有较好的抗冻性能;醚类引气剂可进一步改善混凝土的工作性,其引入的微小气泡可以改善混凝土的包裹性,同时不影响混凝土的抗压强度;混凝土气泡间距系数、平均气孔弦长越小,其抗冻性能越好。

The Influence of Air Entraining Agent on Frost Resistance of Marine Concrete with Manufactured Sand

The effects of different types and contents of air entraining agents and their dosages on the frost resistance of marine concrete with manufactured sand are systematically studied.The mechanism of action of different air entraining agents on marine concrete with manufactured sand under freeze-thaw environment is analyzed by means of pore spacing tests and SEM.The test results show that:when the content of domestic ether air entraining agent is 0.4%,the marine concrete with manufactured sand has better frost resistance.Ether air-entraining agent can further improve the performance of concrete than rosin air-entraining agent.The micro-bubbles introduced by ether air-entraining agent can improve the encapsulation of concrete without affecting the compressive strength of concrete.The smaller the spacing coefficient of air bubbles and the average chord length of pore,the better the frost resistance of concrete.