Creep recovery of plain concrete and its mathematical modelling

Abstract

In order to study creep recovery of plain concrete, an extensive series of creep tests was carried out on normal-strength concrete and high-strength concrete. The main aspects studied are the influence of preloaded stress level, loading age and unloading age on creep recovery. Test results obtained on high-strength concrete and normal-strength concrete are compared, from which the influence of concrete strength on creep recovery is obtained. The experimental results have confirmed that creep recovery is linearly related to the preloaded stress level, and they reveal that both loading age and unloading age have significant influences on creep recovery. However, concrete strength has little influence on creep recovery. Based on the test results, a formula to predict creep recovery has been obtained by making use of an optimization technique.