Title:
Experimental Study on Cyclic Tensile Behavior of Concrete under High Stress Level
Author(s):
Xudong Chen, Jingwu Bu, and Lingyu Xu
Publication:
Materials Journal
Volume:
114
Issue:
5
Appears on pages(s):
775-781
Keywords:
cyclic tensile test; dissipated energy; prediction model; stress level
DOI:
10.14359/51700796
Date:
9/1/2017
Abstract:
Due to the difficulties of direct tensile tests on concrete, available data are limited and conflicting. Cyclic tensile tests on concrete have been carried out by the authors of this paper to investigate the effect of stress level on fatigue behaviors of concrete. Four different stress levels—0.95, 0.90, 0.85, and 0.80—have been employed. The relationship between stress level and fatigue life can be expressed as a logarithmic linear function S = a + blogNf at different probability of failure p, which indicates logarithmic normal distribution can describe the fatigue lives of concrete. The maximum strain accumulation can be distinguished as three typical stages: the rapid accumulation stage, the stable accumulation stage, and the accelerated accumulation stage. The dissipated energy decreases during the first few cycles and then steadily increases as the acceleration to failure is reached. The dissipated energy increases with the increasing of stress levels. As the dissipated energy can reflect both the strength and damping effect of concrete, a power function is selected in this paper to describe the relationship between the fatigue lives and the average dissipated energy. The F-test and t-test of the power model confirm the significance of the averaged dissipated energy in the model. The high value of R2 for the predicted model shows good predictability.