Fundamental Issues Towards Unified Design Theory of Recycled and Natural Aggregate Concrete Components  

作　　者：Jianzhuang Xiao Kaijian Zhang Tao Ding Qingtian Zhang Xuwen Xiao 

机构地区：[1]Department of Structural Engineering,Tongji University,Shanghai 200092,China [2]College of Civil Engineering and Architecture,Guangxi University,Nanning 530004,China [3]College of Civil Engineering,Fuzhou University,Fuzhou 350116,China

出　　处：《Engineering》2023年第10期188-197,共10页工程（英文）

基　　金：the financial support from the Distinguished Young Scholars of China by the National Natural Science Foundation of China(51325802);the National Natural Science Foundation of China(51178340,52078358,and 52008304)。

摘　　要：In the past 20 years,recycled aggregate concrete(RAC),as a type of low-carbon concrete,has become a worldwide focus of research.However,the design methodology for RAC structural components remains a challenge.Consequently,demands for a unified design of natural aggregate concrete(NAC)and RAC components have been presented.Accordingly,this study analyses the necessity of a unified design theory and provides an in-depth demonstration of the strength determination,compressive constitutive relationship,and design method of concrete components.The coefficient of variation of RAC strength is found to be generally higher than that of NAC strength.The compressive and tensile strengths of RAC can be defined and determined using the same method as that used for NAC.The uniaxial compressive constitutive relationship between NAC and RAC has a unified mathematical expression.However,the elastic modulus of RAC decreases,and its brittleness exhibits an increasing trend compared with that of NAC.Finally,to unify the design formulae of RAC and NAC components for bearing capacity,modification factors for RAC components are proposed considering safety and reliability.Additionally,the feasibility of the proposed unified time-dependent design theory is demonstrated in terms of conceptual design and structural measures considering the effects of strength degradation and reinforcement corrosion.It is believed that this study enriches and develops the basic theory of concrete structures.

关 键 词：Recycled aggregate concrete(RAC) Natural aggregate concrete(NAC) Strength determination Constitutive relation Reliability Unified design theory 

分 类 号：R318.08[医药卫生—生物医学工程]