Abstract:
In order to study the effect of freeze-thaw cycles and loading strain rate on the compressive behavior of hydraulic roller compacted concrete, actual mix design and construction technology of hydraulic concrete dam project was considered to prepare specimens, and the freeze-thaw tests with various cycles (0, 25, 50, 75) and dynamic uniaxial compressive tests with different loading strain rates (10
−5/s, 10
−4/s, 10
−3/s, 10
−2/s) were conducted for roller compacted concrete. The freeze-thaw appearance and failure mode subjected to dynamic uniaxial compressive loading and freeze-thaw cycles were analyzed. The effects of freeze-thaw cycles and strain rates on uniaxial compressive strength, peak strain and stress-strain curves were studied, and the corresponding relationship was established based on multiple regression analysis method. The results show that the compressive strength increases linearly with the increasing strain rates and reduces with the increasing freeze-thaw cycles in accordance with two-polynomial relation. The peak strain reduces with the increasing strain rates in accordance with two-polynomial relation, and increases with the increasing strain rates in accordance with two-polynomial relation. By comparing the theoretical stress-strain curves obtained from the constitutive model with the experimental curves, it is revealed that they are in good agreement with the studied range of strain rates and freeze-thaw cycles.