Cyclic compressive stress-strain behaviours of normal weight concrete at Arctic low temperatures

Abstract

To propose more accurate constitutive models for low-temperature concrete structures subjected to cyclic loading, this paper experimentally studied the cyclic compressive behaviours of normal weight concrete (NWC) at low temperatures. Firstly, cyclic compression tests on 36 NWC prisms of C25, C45, and C55 grades were performed at four low-temperature levels, i.e., 20, −30, −60, and − 80 °C. By comparing with monotonic results, it was confirmed that the low-temperature cyclic envelope curves of NWC can be predicted by the corresponding monotonic constitutive models. Furthermore, the effects of low temperatures and grades of NWC on key indexes in constitutive models of NWC under cyclic compression were discussed and analyzed in detail, e.g., plastic strain, stress deterioration ratio, endpoint strain, and damage variable. Through the regression analysis of test data, the cyclic constitutive models composed of the envelope, unloading, and reloading curves were established to describe cyclic stress-strain behaviours of NWC at 20 ∼ −80 °C. Finally, the validations proved that the developed models provided reasonable predictions on low-temperature cyclic response of NWC.