UWBⅡ型水下不分散混凝土絮凝剂的性能研究

Properties of UWBⅡ anti-washout admixtures of underwater concrete

本文针对UWBⅠ型聚丙烯系水下不分散混凝土絮凝剂的缺点,研究了一种由糖类高分子化合物组成的UWBⅡ型絮凝剂。研究结果表明:UWBⅡ型水下不分散混凝土比UWBⅠ型具有更优良的抗分散性能,由UWBⅡ型絮凝剂配制的水下不分散混凝土7d的水陆强度比可达75%—85%,28d可达85%—95%;UWBⅡ型水下不分散混凝土比UWBⅠ型具有更优良的流动性和抗离析性,可保持混凝土的流动性1h以上不损失;UWBⅡ型水下不分散混凝土比UWBⅠ型具有更优良的适应性,对不同产地的水泥及砂石料可保持混凝土的品质稳定,不导致反常的需水量增大。UWBⅡ型水下不分散混凝土,可很好地使用无氯调凝剂调节初凝时间在5h以上,终凝时间在30h内,比UWBⅠ型更方便,对钢筋无腐蚀作用。UWBⅡ型絮凝剂已得到广泛的应用。

This paper is directed against the shortcomings of UWB Ⅰ Anti-washout admixtures subordinated to polyacrylate, and develops a new type of UWB Ⅱ Anti-washout Admixtures subordinated to polysaccharides, It is shown that UWB Ⅱ possesses the more 6xcellent anti-washout property compared with UWB Ⅰ , the compressive strength ratios of cast in water and cast in air of fresh concrete are 75%--85% for 7 days and 85%--95% for 28 days. UWB II also possesses the more excellent flowability and anti-segregation property, flowabiliy retention may be extended over 1 hour. UWB Ⅱ possesses the more excellent compatibility compared with UWB Ⅰ , the more stable fresh concrete can be made by different coarse and fine aggregate and cement produced in different factories, the abnormal increasing in mix water of concrete can not be produced. The initial setting time may be easily controlled beyond 5 hours and final setting time lower than 30 hours by added non chloride accelerators, no corrosion of reinforcement steel can be generated. UWB Ⅱ has been widespread used in various engineering constructions.