Experimental study on the influence of vibration mixing on the characteristics of holes and durability of marine concrete

The pore characteristics and composition of concrete affect its strength and durability. In order to improve the service life of marine concrete, this paper conducted experimental research on the performance of high-performance marine concrete based on vibration mixing. Comparative experiments were conducted on the water absorption performance, pore structure characteristics, load, and chloride ion diffusion of C30 and C50 concrete prepared by vibration mixing and ordinary mixing, and different grades of concrete were compared and studied. The experimental results show that compared with ordinary mixing, the average water absorption rate of C30 and C50 marine concrete under vibration mixing was reduced by 30.8% and 28.9%, respectively; The coefficients of variation were 1.8% and 1.5%, respectively, and the reduction was 75.4% and 75.8%. The average pore size of C30 and C50 concrete specimens subjected to vibration mixing was 72.68 nm and 55.9 nm, respectively, with porosity rates of 22.1% and 15.8%, respectively. Compared with ordinary mixing, the average pore size decreased by 32.7% and 32.1%, and the porosity rate decreased by 51.4% and 53.3%, respectively. The chloride ion diffusion coefficients of C30 and C50 concrete were reduced by 20.4% and 19.8% after 90 days of vibration mixing in a 2.5% sodium chloride environment and a 50% stress ratio. The study shows that vibration mixing improves the pore structure characteristics of marine concrete, improves the density of concrete, enhances the durability of concrete, providing new technologies for the future design and construction of marine concrete in marine transportation and other marine ancillary projects.