Experimental study on the frost resistance of molybdenum tailings concrete

The research aims to experimentally investigate the frost resistance of molybdenum tailings concrete (MoTC), involving C30 and C60 grade, with varying molybdenum tailings replacement ratios and freeze-thaw cycles. The results indicated that with an increase in the number of freeze-thaw cycles, both C30 and C60 grade MoTC showed an aggravated deterioration in strength and failure morphology. However, the deterioration of C60 grade MoTC was less severe than C30 grade. The more than 25% addition of molybdenum tailings significantly improved the frost resistance of C30 grade MoTC, but had minor effect on that of C60 grade MoTC. The mass loss ratio, cubic compressive strength, and dynamic elastic modulus of both C30 and C60 grade MoTC decreased with the increase in freeze-thaw cycles. The highest mass loss ratio for C30 grade MoTC was 100%, with the total loss of the dynamic elastic modulus and cubic compressive strength. For C60 grade MoTC, the highest mass loss ratio was 2.13%, with dynamic elastic modulus and cubic compressive strength reaching 12.8 and 23.79 MPa, respectively. Based on the test data, a predictive formula for the dynamic elastic modulus of C30 grade MoTC with considering the molybdenum tailings replacement ratios and freeze-thaw cycles was proposed, which shows good agreement between the results.