Abstract:Combined with the relevant literature and the usage of the mix proportion in the project, by comparing the P.O42.5 grade cement C30 pile foundation mix proportion and the P.II 52.5 grade C30 pile foundation mixed sand mix proportion, after calculation, the cement slurry to aggregate ratio of the two is basically the same, and the latter has better durability and economy. Based on this, during the construction process of high-performance marine concrete with C40, C45 and C50 pier column mixed sand, the statistics of partial compressive strength and the detection of chloride ion diffusion coefficient are found that in terms of mechanical properties, the compressive strength of 28 d concrete meets the design requirements and is relatively stable. The strength of 56 d increases significantly, while the strength of 90 d slows down. In terms of durability, the chloride ion diffusion coefficient of 56 d is less than 3×10-12 m2/s. Therefore, in general, the use of P.II52.5 cement to design the mix proportion, strength and durability of high-performance marine concrete with mixed sand can meet the requirements, which also has the significant economic effects.