骆马湖砂对预拌混凝土的影响及应对措施

Influence and Measures of Luoma Lake Sand on Ready-mixed Concrete

对于工程中骆马湖砂导致预拌混凝土坍落度损失过快的问题,对骆马湖砂的含泥量、泥块含量、细度模数、饱和面干吸水率进行了测试,分析了泥对净浆和砂浆的影响,试验了分别掺加聚丙烯酸钠、季铵盐类低聚物和腐殖酸钠三种功能助剂对骆马湖砂中泥的屏蔽效果,在减水剂掺量为胶材用量的1.4%、聚丙烯酸钠掺量为0.3%或季铵盐类低聚物的掺量为0.4%时,混凝土坍落度具有较好的保持能力,1h无损失,且均能满足混凝土强度设计要求。

Aiming at the project of Luoma Lake sand in ready-mixed concrete slump loss too quick, the Luoma Lake sand clay content, clay content, fineness modulus and saturated surface dry water absorption were tested, and the influence of mud on the pure paste and mortar was analyzed. The shielding effect of adding sodium polyaerylate, quaternary ammoni- um salt oligomer and sodium humic acid on the Luoma Lake sand mud was tested. When the content of water reducing a- gent for cement amount was 1.4%, sodium polyacrylate admixture dosage was 0.3% or quaternary ammonium salt oligomer was 0.4%, the slump of concrete has good ability, 1 hour without loss, and the concrete can meet the design requirements of strength.