Experimental and Theoretical Analyses on the Density and Modulus Development of Concrete Under Continued Hydration  

作　　者：Lanzhen Yu Jiankang Chen Hui Song 

机构地区：[1]The Faculty of Mechanical Engineering and Mechanics, Ningbo University, Ningbo 315211, China [2]State Key Laboratory of Turbulence and Complex Systems, Peking University, Beijing 100871, China [3]Department of Architectural Engineering, Ningbo Polytechnic, Ningbo 315800, China

出　　处：《Acta Mechanica Solida Sinica》2018年第2期161-173,共13页固体力学学报（英文版）

基　　金：the financial support by the National Natural Science Foundation of China (NSFC#11772164,#11272165,#11572163);the National Basic Research Program of China (973 Program,2009CB623203);the Key Research Program of Society Development of Ningbo (2013C51007);the K.C.Wong Magna Fund in Ningbo University;supported by the Research Project Foundation of Zhejiang Educational Department (Y201636745)

摘　　要：In this paper, new models of the density and modulus development of concrete under continued hydration were studied. Experimental study was performed for different mixes of concrete. To avoid considering the effect of variation of Poisson＇s ratio, the one-dimensional ultrasonic technique was adopted to detect the modulus development of concrete under continued hydration. The experimental results indicate the nonlinear characteristics of density and modulus evolution. At the initial stage of continued hydration, the density and modulus increase quickly, and then the increases slow down and finally tend to be constant. The mechanism of modulus enhancement is that the newly produced C-S-H gel in the continued hydration process not only leads to the decrease in porosity, but also repairs the initial defects of concrete. Based on this mechanism, simple differential equations for the density and modulus development of concrete were established by considering the chemical reactions of continued hydration, and new simple models for density and modulus development were proposed.In this paper, new models of the density and modulus development of concrete under continued hydration were studied. Experimental study was performed for different mixes of concrete. To avoid considering the effect of variation of Poisson＇s ratio, the one-dimensional ultrasonic technique was adopted to detect the modulus development of concrete under continued hydration. The experimental results indicate the nonlinear characteristics of density and modulus evolution. At the initial stage of continued hydration, the density and modulus increase quickly, and then the increases slow down and finally tend to be constant. The mechanism of modulus enhancement is that the newly produced C-S-H gel in the continued hydration process not only leads to the decrease in porosity, but also repairs the initial defects of concrete. Based on this mechanism, simple differential equations for the density and modulus development of concrete were established by considering the chemical reactions of continued hydration, and new simple models for density and modulus development were proposed.

关 键 词：CONCRETE Continued hydration Density development Modulus development Ultrasonic 

分 类 号：TU528[建筑科学—建筑技术科学]