Hydration-Strength-Workability-Durability of Binary, Ternary, and Quaternary Composite Pastes.

Yi Han,Run-Sheng Lin,Xiao-Yong Wang,Seokhoon Oh

doi:10.3390/ma15010204

Abstract

At present, reducing carbon emissions is an urgent problem that needs to be solved in the cement industry. This study used three mineral admixtures materials: limestone powder (0–10%), metakaolin (0–15%), and fly ash (0–30%). Binary, ternary, and quaternary pastes were prepared, and the specimens’ workability, compressive strength, ultrasonic pulse speed, surface resistivity, and the heat of hydration were studied; X-ray diffraction and attenuated total reflection Fourier transform infrared tests were conducted. In addition, the influence of supplementary cementitious materials on the compressive strength and durability of the blended paste and the sustainable development of the quaternary-blended paste was analyzed. The experimental results are summarized as follows: (1) metakaolin can reduce the workability of cement paste; (2) the addition of alternative materials can promote cement hydration and help improve long-term compressive strength; (3) surface resistivity tests show that adding alternative materials can increase the value of surface resistivity; (4) the quaternary-blended paste can greatly reduce the accumulated heat of hydration; (5) increasing the amount of supplementary cementitious materials can effectively reduce carbon emissions compared with pure cement paste. In summary, the quaternary-blended paste has great advantages in terms of durability and sustainability and has good development prospects.

Highlights

Human-made carbon dioxide emissions are an important cause of global climate change, and cement production accounts for 5–8% of human-made carbon dioxide emissions [1,2,3]
The results showed that the addition of waste red gypsum effectively reduces the gas foaming rate and can increase the compressive strength of aerated concrete (AAC)
The gaps this study bridged compared to currently existing work are summarized as follows: (1) we compared the workability of binary, ternary, and quaternary-blended pastes using LS powder, MK, and fly ash (FA) as alternative materials; (2) we studied the early compressive strength and hydration performance of the ordinary Portland cement (OPC)–LS–MK–FA quaternary-blended paste, and the correlation between the compressive strength and the heat of hydration; (3) we studied the durability of the OPC–LS–MK–FA quaternary-blended pastes; (4) we conducted X-ray diffraction (XRD) and attenuated total reflection Fourier transform infrared (ATR-FTIR) tests to study the microstructure of the quaternary-blended paste

Summary

Introduction

Human-made carbon dioxide emissions are an important cause of global climate change, and cement production accounts for 5–8% of human-made carbon dioxide emissions [1,2,3]. With the development of industry and infrastructure, the demand for cement will increase substantially; carbon dioxide emissions will continue to grow predictably [4,5]. At present, reducing cement carbon dioxide emissions has become an urgent problem that must be solved. Supplementary cementitious materials (SCMs) application, recycled concrete, carbon capture, utilization, and storage are common technical solutions to reduce carbon dioxide emissions [6]. Among them, using SCMs to replace cement can reduce carbon dioxide emissions by 30 and 40% and is currently the most economical and effective method [7,8]. The use of some industrial by-products can improve the problem of environmental dust pollution

Methods

Results

Conclusion