{"title":"Performance and hydration mechanisms of ultrafine iron ore tailings enhanced supersulfated cement with high phosphogypsum content","authors":"Mingzhe Zhang , Bing Chen , Weisheng Zhu","doi":"10.1016/j.cemconcomp.2024.105891","DOIUrl":null,"url":null,"abstract":"<div><div>This study systematically investigates the influence of ultrafine iron ore tailings (UIOT) on the performance and hydration process of supersulfated cement (SSC) with high phosphogypsum (PG) content. UIOT incorporation retards early-age strength but enhances later-age strength, with a 20 % replacement ratio of granulated blast furnace slag (GBFS) leading to a 52 % increase in 28-day compressive strength. The performance improvement can be primarily attributed to the following aspects: in the first instance, UIOT regulates the formation rate of ettringite (AFt) by promoting the formation of Fe-Al-bearing AFt ((Fe, Al)-AFt), thereby reducing the excessive formation of AFt typically observed in high-gypsum blended systems. Furthermore, UIOT promotes the formation of calcium-alumino-silicate hydrate (C-(A)-S-H) gel and optimizes the Si/Ca ratio of the gel. The unreacted UIOT particles also play a physical filling role, contributing to the performance enhancement.</div></div>","PeriodicalId":9865,"journal":{"name":"Cement & concrete composites","volume":"157 ","pages":"Article 105891"},"PeriodicalIF":10.8000,"publicationDate":"2024-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Cement & concrete composites","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0958946524004645","RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CONSTRUCTION & BUILDING TECHNOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
This study systematically investigates the influence of ultrafine iron ore tailings (UIOT) on the performance and hydration process of supersulfated cement (SSC) with high phosphogypsum (PG) content. UIOT incorporation retards early-age strength but enhances later-age strength, with a 20 % replacement ratio of granulated blast furnace slag (GBFS) leading to a 52 % increase in 28-day compressive strength. The performance improvement can be primarily attributed to the following aspects: in the first instance, UIOT regulates the formation rate of ettringite (AFt) by promoting the formation of Fe-Al-bearing AFt ((Fe, Al)-AFt), thereby reducing the excessive formation of AFt typically observed in high-gypsum blended systems. Furthermore, UIOT promotes the formation of calcium-alumino-silicate hydrate (C-(A)-S-H) gel and optimizes the Si/Ca ratio of the gel. The unreacted UIOT particles also play a physical filling role, contributing to the performance enhancement.
期刊介绍:
Cement & concrete composites focuses on advancements in cement-concrete composite technology and the production, use, and performance of cement-based construction materials. It covers a wide range of materials, including fiber-reinforced composites, polymer composites, ferrocement, and those incorporating special aggregates or waste materials. Major themes include microstructure, material properties, testing, durability, mechanics, modeling, design, fabrication, and practical applications. The journal welcomes papers on structural behavior, field studies, repair and maintenance, serviceability, and sustainability. It aims to enhance understanding, provide a platform for unconventional materials, promote low-cost energy-saving materials, and bridge the gap between materials science, engineering, and construction. Special issues on emerging topics are also published to encourage collaboration between materials scientists, engineers, designers, and fabricators.