Estimating long-term creep and shrinkage of high-strength concrete

This paper presents the development of formulas to estimate the long-term creep and shrinkage of high-strength concrete. The experimental part of the work focused on concrete mixes having a fixed water/binder ratio of 0.35 and a constant total binder content of 500 kg/m3. The percentages of silica fume that replaced cement in this research were: 0%, 6%, 8%, 10% and 15%. According to the experimental results some equations are proposed for predicting the time-dependent behaviour of high-strength concrete. Based upon a survey of published experimental data, the accuracy of the proposed equations compares favorably with that of several common methods, which were developed for estimating the creep and shrinkage of normal strength concrete. Also, according to the experimental work, it is shown that to improve the estimation of long-term deformations of high-strength concrete utilizing the ACI and CEB methods, the results of short-term tests should be substituted into them.