Bayesian approach for quantifying silica fume and water reducer impact on creep of concrete

摘要

The behaviour of concrete structures is affected by the time-dependent volume changes of concrete caused by sustained loads and moisture loss. Creep deformations have an important effect on long-term integrity of reinforced concrete structures. Incorrect or inaccurate prediction of these volume changes leads to undesirable and harmful consequences for the structures. Knowing that the Eurocode 2 does not take admixtures and additives into consideration in predicting creep deformations, the aim of this study is to apply correction coefficients to the Eurocode 2 creep formulas to take into account the effect of additives and admixtures, especially silica fume and water reducer. A large database from international laboratories and research centres is used in this study. The first step consists of comparing experimental measurements of creep deformations with creep values predicted by the Eurocode 2 formulas. The second step lies in introducing correction coefficients to the creep formulas of Eurocode 2, taking into consideration the percentage of admixtures and additives. These new correction coefficients are introduced in the Eurocode 2 formulas using an approximate Bayesian computation method based on a rejection algorithm.