Research on Dynamic Compressive Performance of Polypropylene Fiber-Reinforced High-Strength Concrete under Freeze-Thaw Environment

Abstract

Existing studies have proved that the incorporation of polypropylene fiber can effectively improve the impact resistance of concrete. In this paper, the split Hopkinson pressure bar and digital pulse shaping technology are used to further study the dynamic compression performance and constitutive relationship of concrete in the cold regions under the deteriorating effect of freeze-thaw cycle, and obtain the dynamic increase factor. Studies have shown that polypropylene fiber-reinforced high-strength concrete has a strain rate enhancement effect. The number of freeze-thaw cycle times at low strain rates has an obvious effect on concrete deterioration, and the effect is weaker at higher strain rates. By comparing three typical dynamic strength growth factor models with the test results, after revising the model, the dynamic increase factor equations under different freeze-thaw circulation times were fitted. This research provides a basis for the design of durability and robustness of building structures in cold regions.

Study on Mechanical Properties of Concrete at Different Ages under Freeze-Thaw Cycles in Plateau

“…Severe freeze-thaw cycle damage often occurs in some areas, including civil buildings, highways, railway projects and other infrastructure. The damage of engineering construction facilities mainly occurs on the concrete materials with a large amount of use, which affects the overall durability of the concrete structure [2][3].…”