关键词: 混凝土;改性机理;矿物质材料;聚合物;纤维

Abstract: The traditional cement concrete has the shortcomings such as low tensile strength, large brittleness, slow condensation hardening, large shrinkage, and so on.So it cannot meet the needs of the actual engineering.At present, domestic and foreign researchers have studied the modification of ordinary concrete by mineral additives, polymers, fibers and other materials to improve its comprehensive performance, and achieved remarkable results.The results of concrete modification are systematically summarized from the above three aspects.The modification mechanism of modified concrete and its effect on concrete performance are analyzed comprehensively.It is considered that the choice of modified materials is related to the economy of materials, the test technology, the modification effect, and so on. The polymer emulsion and the fiber material are the most widely studied materials.The concrete modification should pay attention to improve the cohesive force between the modified material and the uniform dispersion of the aggregate in the concrete. Although the existing polymer modification mechanism model is constantly improving, it cannot fully explain the modification mechanism of soluble polymer to concrete.The performance of modified concrete by graphene, graphene fiber and nano carbon fiber materials should to be further studied, which materials have a good prospect of application.

Key words: concrete;modification mechanism;mineral material;polymer;fiber