2013 Volume 11 Issue 2 Pages 35-48
This paper describes a method for estimating creep deformations of PVA-ECC under high stress levels from short-term tests. To obtain necessary data, a series of accelerated bending and compression creep tests under a sequence of increasing loads were carried out. Of particular interest was to study the evolution of plasticity and damage under varying load levels, and thus allow the rate of plasticity and fracturing as functions of evolving strain and fracture to be determined. Based on these behavioral aspects, predictions of creep of ECC at high stress levels were made. It is found that creep rupture in flexure and compression occurs at nearly the same order of lifetime in a logarithm scale, being the rupture at 90% of flexural strength about one order longer than that under compression. The tensile and compressive strains at rupture, when the load level is decreased from 90% to 75% of the short-term strength, are 1.1-1.4 and 1.6-3.5 times the short-term tensile and compression strain capacities, respectively.