Study of the influence of modern superplastificators on the properties of road cement concrete

Abstract

Abstract. In the technology of road concrete, the use of plasticizing additives is mandatory. In the last century, the most widely used plasticizers are lignosulfonates. These additives reduce the water demand of concrete mixtures by 10...15 % and increase the strength of concrete by 20...25 %. However, the presence of sugars in their composition leads to a strong slowdown of the hardening processes and can lead to a decrease the strength of concrete at the age of 28 days. In this century, modern superplasticizers based on polycarboxylates began to be widely used in industrial and civil construction. They were mainly used for the manufacture of cast concrete mixtures. On the other hand, their use in moderately mobile concrete mixes allows reducing water demand by 35...40 % and increasing strength by 60...100 % compared to concretes without additives. However, in such mixtures the use of polycarboxylates leads to a quick setting of the ce-ment and an accelerated set of concrete strength. This does not meet the requirements of the road concrete standards. The goal of the work is to study the influence of modern chemical additives of various nature on the basic properties of road cement con-crete. The article is devoted to the actual problem of the effective use of polycarboxylate superplasticizers