Reliability Analysis of Freeze-Thaw Damage of Recycled Ceramic Powder Concrete

In order to improve the recycling efficiency of waste ceramic powder, the effect of ceramic powder on the freeze-thaw resistance of recycled concrete under different substitution rates is studied in view of the poor frost resistance of recycled concrete. Six groups of mixtures with ceramic powder substitution rates of 0%, 10%, 20%, 30%, 40%, and 50% are designed. Before the test, the porosity distribution, porosity, and permeability of each group of specimens are calculated based on the principle of nuclear magnetic resonance (NMR), and the relationship between porosity and permeability of recycled concrete with ceramic powder is established by MATLAB. After a round of freeze-thaw cycle, the mass loss rate and relative dynamic modulus of each group of specimens are measured. Based on the Palmgren theory, the reliability calculation model of freeze-thaw damage is established, and the residual life of each group of specimens is predicted. The results show that the dynamic modulus of elasticity decreases, and the mass loss rate first increases and then decreases. When the replacement rate of ceramic powder is 20%, the porosity and permeability of recycled concrete with ceramic powder are the smallest, and the freeze-thaw cycle resistance is the strongest. In addition, the reliability calculation model of freeze-thaw damage based on the Palmgren model has high reliability, which can directly reflect the relationship between the reliability of recycled ceramic powder concrete and freeze-thaw cycle and can be well applied in practical application.