| As the important constituent, using of chemical admixtures in high performance concrete is becoming very common. But the research on the influence of chemical admixtures on shrinkage of high performance concrete seems too insufficient, and the existing results are chaos.Through the perpendicular experiment, the main effecting factors on the shrinkage of cement mortar with low were analyzed. Based on the above research, in the mortar with constant water content, paste volume content and aggregate content, the influence of three types superplasticizer(naphthalene series, aminosulfonic acid series and polycarboxylic acid series superplasticizer) on shrinkage was studied, and the reason of the influence was analyzed also.Then, adding mineral admixtures and superplasticizers, the influence of superplasticizer on shrinkage of the mortar with constant water-binder ratio and sand-binder ratio was studied.And finally, using the same raw materials, mixture proportions and test condition, the influence of superplasticizers on shrinkage of concrete was studied, and the relationship of shrinkage between concrete and mortar was analyzed also.The results show that the shrinkage of concrete is linear with the shrinkage of the mortar with same raw materials, mixture proportions and test conditions. And adding superplasticizer in the mortar or concrete with constant mixture proportion can increase its shrinkage, but adding mineral admixtures can reduce the influence of the superplasticizer on the shrinkage. Besides, selecting the kind and quantity of superplasticizer and mineral additions can decrease the shrinkage of mortar or concrete. Generally, The influence of naphthalene series superplasticizer (e.g. HJUNF-2A or THS-1) on the shrinkage is more than aminosulfonic acid series superplasticizer (e.g. ASP-L), but the influence of polycarboxylic acid series superplasticizer (e.g. CABR) on the shrinkage is less than the above two types superplasticizer.
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