The performance of high-performance concrete in addition to the impact of the construction process, mainly by the impact of raw materials. Only to meet the high performance requirements of raw materials, in order to prepare in line with high-performance design requirements of high-performance concrete. Selection of raw materials, should be based on the actual requirements of the project and the environment in which the general configuration of high strength concrete materials are gelled materials, coarse aggregate, superplasticizer. Due to the difference, high strength and low water-cement ratio are no longer inversely proportional. But so far, the world has no suitable method for designing high-performance concrete mixes. Researchers in each country on the basis of their own experiments, roughly calculate the specific mix. And then through a number of adjustments to determine the more appropriate mix ratio, so in the mix of this research is not yet mature. Foreign scholars in the study of HPC more attention to reduce the HPC self-shrinkage and delayed ettringite on the impact of HPC, in sharp contrast to the Chinese scholars for the use of expansion agent to compensate for HPC dry shrinkage and self-shrinkage Has a profound theory and long-term practice. First of all, it is certain that it is certainly beneficial for HPC to incorporate any amount of bulking agent, depending on which function, from the firmness, the volume stability, and the relief. Long-term study found that HPC early strength growth fast, shrinkage, general expansion agent expansion rate is small, can not compensate for the early contraction of HPC to achieve a better compensation, so some experts try to add in the expansion agent fine admixture and other substances Improve this phenomenon. After a long exploration, it was found that the limiting expansion rate of the specimen after adding fly ash was decreased and the strength was increased, and the coordinated development of expansion and strength was further proposed.
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