Effect of initial temperature damage on the static and fatigue performance of all-lightweight shale ceramsite concrete

The effects of initial temperature damage on the static and compressive fatigue properties of LC30 all-lightweight shale ceramsite concrete (ALWSCC) were studied. The curing conditions ranged from −5 °C to −30 °C without antifreeze, with an elevated temperature range of 100 °C to 400 °C applied after 28 days of standard curing. We tested the static strength, elastic modulus, and stressstrain curves of ALWSCC, as well as its uniaxial compression fatigue life and ƐN curves under different stress levels. The credibility of data from only three test samples per condition was statistically analyzed, and we explored how temperature, aggregate properties, and concrete pore structure affect performance. The results indicate that the impact of temperature on the static and fatigue performance of ALWSCC can be described by a unified damage model. The Hillerborg characteristic length effectively captures the brittleness induced by temperature changes. Using the two-parameter Weibull equation and various fatigue equations that account for failure probability and temperature, the fatigue life predictions were accurate. Although low and high temperatures affect ALWSCC differently, temperature effects combined with static and fatigue loads further accelerate its deterioration. [Display omitted] •The initial temperature damage will aggravate the static and fatigue deterioration of concrete.•An intrinsic relationship exists between the fatigue performance of concrete and the Hillerborg characteristic length.•The fatigue equation can be described by Weibull parameter, failure probability and temperature.