新型粘度改性材料对自密实混凝土性能的影响

Influence of a New Viscosity Modifier on Properties of Self-Compacting Concrete

为提高自密实混凝土的工作性能,特别是间隙通过性和填充性,通过特殊矿物掺合料和功能外加剂复配,配制出了一种新型的粘度改性材料。在实验室制备了C40自密实混凝土,依据相关规范进行试验,测试粘度改性材料对碎石粒径、河砂细度模数的适应性,以及对混凝土用水量敏感性、力学性能、干燥收缩的影响。试验结果表明:粘度改性材料可明显提升自密实混凝土的工作性能,并且可在一定程度上降低自密实混凝土对原材料砂石的敏感性,降低自密实混凝土对用水量的敏感性,用水量敏感度达到15kg/m^2,同时不影响自密实混凝土的后期强度发展和28d收缩率。

To improve the working performance of the self-compacting concrete, especially its gap passing and filling capacity, a kind of new viscosity modifier has been made by the proper mix-ing of the special mineral admixtures and functional admixtures. And C40 self-compacting concrete was prepared in the lab to test the adaptability of the viscosity modifier to the gravel particle size and river sand fineness modulus and the influence of the viscosity modifier on the water sensitivity, mechanical behavior and drying shrinkage of concrete. The results of the test show that the viscos-ity modifier can improve the working performance of the self-compacting concrete and reduce the sensitivity of the self-compacting concrete to the sands and gravels to a certain extent, and reduce the water sensitivity of the self-compacting concrete as well, which makes the water sensitivity reaches up to 15 kg/m2 and will not influence the subsequent strength and shrinkage of 28 d of the self-compacting concrete.