摘要
Factors that have effect on concrete creep include mixture composition,curing conditions,ambient exposure conditions,and element geometry.Considering concrete mixtures influence and in order to improve the prediction of prestress loss in important structures,an experimental test under laboratory conditions was carried out to investigate compression creep of two high performance concrete mixtures used for prestressed members in one bridge.Based on the experimental results,a power exponent function of creep degree for structural numerical analysis was used to model the creep degree of two HPCs,and two series of parameters of this function for two HPCs were calculated with evolution program optimum method.The experimental data was compared with CEB-FIP 90 and ACI 209(92) models,and the two code models both overestimated creep degrees of the two HPCs.So it is recommended that the power exponent function should be used in this bridge structure analysis.
Factors that have effect on concrete creep include mixture composition, curing conditions, ambient exposure conditions, and element geometry. Considering concrete mixtures influence and in order to improve the prediction of prestress loss in important structures, an experimental test under laboratory conditions was carried out to investigate compression creep of two high performance concrete mixtures used for prestressed members in one bridge. Based on the experimental results, a power exponent function of creep degree for structural numerical analysis was used to model the creep degree of two HPCs, and two series of parameters of this function for two HPCs were calculated with evolution program optimum method. The experimental data was compared with CEB-FIP 90 and ACI 209(92) models, and the two code models both overestimated creep degrees of the two HPCs. So it is recommended that the power exponent function should be used in this bridge structure analysis.
