考虑基体混凝土水灰比影响的再生粗(细)骨料混凝土徐变模型

Existing research shows that the inclusion of fine recycled aggregate (FRA) with different strength of matrix concrete has different influences on the creep behavior of recycled aggregate concrete (RAC). However, the available creep models do not account for the influence of matrix concrete strength on the creep of RAC.Thus, based on the existing creep model of RAC, this paper proposed a new general creep model by introducing the coefficient of water-cement ratio to account for the influence of matrix concrete strength on physical properties of residual cement paste. The predicted results of this model and other creep models were compared with the available creep tests of RAC. The comparative results show that the newly proposed model has the best performance in predicting the creep of RAC with the lowest scatter. Extensive parametric study was then performed to investigate the influence of commonly-used study parameters on the creep of RAC. It is shown that the strength of matrix concrete, the water absorption of FRA, the replacement ratio and the relative humidity are the key factors influencing the creep of RAC.