Damage of concrete subjected to simultaneous fatigue load and thermal effect

Abstract

Physical loads and environmental actions have simultaneous effects on concrete in nature. An analytical method is proposed to detect the damage to concrete subjected to four-point flexure fatigue load and thermal hysteresis in freeze–thaw. The interaction of the two kinds of loads on the combined damage, in terms of a coefficient fD(T), is defined to characterise quantification. Damage is aggravated by the combined loads when fD(N)>1 as compared to isolated loading. The results show that increasing fD(N) is always seen in the freezing stage, since damage as a result of tensile stress only is being considered here. Moreover, a critical point above which the damage is aggravated by the combined loads is found by extrapolating the maximum values of fD(N) until fD(N)=1 at N = 380 000, that is close to the average life (N = 348 310) obtained from the experiments. This work provides a framework to explore the coupled effects on damage from physical loads and environmental actions.

Nonlinear elastic response of thermally damaged consolidated granular media

“…The evolution of the microstructure in the presence of large spatial-temporal thermal gradients needs to be detected and characterized for improving models of the material's mechanical response and of its evolution in correspondence of different thermal loadings. [25][26][27][28] Together with the modeling improvement, the experimental detection of thermal damage in the early stages, when, e.g., cracks are not yet visible on the surface of the sample, is of paramount importance for preventive intervention.…”

A review of concrete properties under the combined effect of fatigue and corrosion from a material perspective

“…By using flexural fatigue loading on concrete specimens in an environment chamber in which liquid nitrogen was used as a cryogen to produce a closed freeze-thaw environment without water uptake, as shown in Fig. 8, Li et al [134,135] monitored the damage process of a concrete sample under the coupling effect of fatigue loading and FTCs by using acoustic emission technology. The residual strain of concrete under this coupling action was greater than that under a single action.…”

Thermal Analysis of a Raft Concrete Foundation: A Case Study of a Leaking Ethane Tank

“…For steel reinforcement subjected to low temperature, experiments have shown that reinforced bars tend to become brittle when exposed to extremely low-temperature environments (less than −20 • C) [11][12][13][14][15]. Other studies have also investigated fatigue and thermal effects on concrete [17]. On the other hand, test results indicate that steel reinforcement subjected to extreme low temperature (below −20 • C) tends to become brittle.…”