Renmin Zhujiang (Jan 2023)
Constitutive Model of Recycled Aggregate Concrete for Channels Affected by Freeze-Thaw Damage
Abstract
The stress-strain constitutive relationship is an important research content of concrete materials.To reveal the mechanical damage law of recycled aggregate concrete under the effect of freeze-thaw cycles,this study builds a statistical model of mesoscopic damage to concrete on the basis of Weibull strength theory and compression experiment results of concrete.The results show that the damage to concrete under the uniaxial load is more significant under the action of the freeze-thaw cycle.As the number of freeze-thaw cycles increases from 0 to 120,the compressive strength and elastic modulus decrease exponentially,and the failure strain shows an upward trend.The Weibull strength theory is employed to construct the constitutive model of concrete damage considering the influences of freeze-thaw cycles,and by fitting,the shape parameter m and the scale parameter ε0 are solved.In addition,the number of freeze-thaw cycles T is introduced to this model.The comparison of the measured stress-strain curve with the fitted results of the model verifies the rationality of the theoretical model.
