Creep Failure of Concrete under High Stress

Creep failure is due to the interconnection of microcracks in concrete when the material is placed under continual high stress. High-stress creep failure is a rarely researched phenomenon and currently lacks mathematical explanation. Previous investigations of high-stress creep failure in concrete from around the world have shown that shorter product duration and smaller creep strain are correlated to higher stress levels, while the loading age and concrete strength had little effect on high-stress creep failure. In addition, critical stress levels were not found to be dependent on loading age or concrete strength. The investigated critical stress level, eta= sigma/f(c), varied from 0.75 to 0.8, with a recommended level of 0.76. This article investigates the relationships among stress level, failure time, and failure strain analyzed from 175 reports collected from around the world. Additionally, we propose a quantitative high-stress creep failure law.