The Influence and Application of Slag, Fly Ash, and Limestone Flour on Compressive Strength of Concrete Based on the Concrete Compressive Strength Development over Time (CCSDOT) Model

Jian Zheng,Guohua Liu

doi:10.3390/app10103572

Abstract

Concrete and cement have been widely used in past decades as a result of urbanization. More and more supplementary cementitious materials are adopted in concrete because its production complements environmental conservation. The influence of slag, fly ash, limestone, etc., on compressive strength of concrete is of interest to engineers worldwide. Many previous studies were specific to certain engineering or certain experiments that could not reveal the nature of the influence of the three supplementary cementitious materials on concrete’s compressive strength. The research concerning the influence of two or more kinds of supplementary cementitious materials on concrete’s compressive strength is still unclear. Moreover, there is a lack of clarity on the optimum proportion of one or more certain cementitious materials in practical engineering or experiments. To overcome these problems, this study adopts the concrete compressive strength development over time (CCSDOT) model, which generates an explicit formula to conduct quantitative research based on extensive data. The CCSDOT model performs well in fitting the compressive strength development of concrete containing cement, slag, fly ash, and limestone flour. The results reveal the nature of the influence of the three supplementary cementitious materials on concrete’s compressive strength through the parameter analysis in the model. Two application cases are analyzed concerning the selection of the three supplementary cementitious materials and design of concrete mix proportion for practical engineering. It is concluded that the CCSDOT model and the method in this study can possibly provide guidance on both the selection of supplementary cementitious materials and the design of optimal concrete mix proportion for practical engineering. Therefore, the study is highly essential and useful.

Highlights

In recent years, urbanization and the rapid development of large-scale infrastructure have created a huge demand for concrete and Portland cement [1]
There were 239 groups of concrete mix proportions (139 groups of concrete containing fly ash, 12 groups of concrete mixed with fly ash and limestone flour, 85 groups incorporated with fly ash and slag, 3 groups of concrete incorporated with limestone flour) from 18 practical engineering and lab reports adopted in this study
An intuitive comparison between the fitted value and the tested value of concrete compressive strength is shown in Figure 3, including concrete incorporated with fly ash (FA), concrete mixed with fly ash and limestone flour (FA + LF), concrete incorporated with fly ash and slag (FA + SL) and concrete mixed with limestone flour (LF)

Summary

Introduction

Urbanization and the rapid development of large-scale infrastructure have created a huge demand for concrete and Portland cement [1]. Considering environmental protection, energy conservation, and resource benefits [2], more and more supplementary cementitious materials, including slag [3], fly ash [4], and limestone flour [5], are added into concrete as partial cement replacement material. The three supplementary cementitious materials have significant influence on. Sci. 2020, 10, 3572 the compressive strength of concrete [6]. Compressive strength is assumed to be one of the most important and essential properties of concrete, since it usually shows the overall quality of concrete [7]

Methods

Results

Discussion

Conclusion