单轴受压地质聚合物再生混凝土损伤特性及本构模型研究

Damage Characteristics and Constitutive Model of Geopolymer Recycled Concrete under Uniaxial Compression

建筑固体废弃物与工业固体废弃物的协同、高效处置对固体废弃物的综合利用有着重要意义。本文采用CT扫描技术与数字体相关法,对单轴受压地质聚合物再生混凝土的损伤演化特性进行分析,并以此建立单轴受压地质聚合物再生混凝土损伤本构模型。研究结果表明,地质聚合物再生混凝土内部非均匀应变场的产生是其发生破坏的主要原因,考虑数值特征和空间特征的损伤因子与应变呈5次函数关系,基于应变等效原理建立的损伤本构模型可以较好地表征在荷载作用下的应力-应变关系。本研究可以为地质聚合物再生混凝土在工程上的应用提供理论基础和技术支撑,同时为再生混凝土的力学损伤研究提供新方法。

The collaborative and efficient disposal of construction solid waste and industrial solid waste is of great significance to the comprehensive utilization of solid waste. In this paper, CT scanning technology and digital volume correlation method were used to analyze the damage evolution characteristics of geopolymer recycled concrete under uniaxial compression, so as to establish the damage constitutive model of geopolymer recycled concrete under uniaxial compression. The results show that the main reason for the failure of geopolymer recycled concrete is the generation of non-uniform strain field. The damage parameter and strain present a quintic function relationship considering the numerical and spatial characteristics. The damage constitutive model based on the strain equivalence principle can better characterize the stress-strain relationship under load. This research can provide theoretical basis and technical support for the application of geopolymer recycled concrete in engineering, and provide a new method for the study of mechanical damage of recycled concrete.