Enhancing workability of high-volume calcined clay blend cement pastes through optimized addition sequences of PCE superplasticizer

被引：3

作者：

Ren, Jun ^{[1
]}

Guo, Jinyi ^{[1
]}

Jin, Yu ^{[2
]}

Liu, Fan ^{[1
]}

Liu, Birunxuan ^{[1
]}

Yan, Shuo ^{[1
]}

Yan, Wei ^{[1
]}

Lu, Caimeng ^{[3
]}

Shi, Shi ^{[4
]}

机构：

[1] Yunnan Univ, Urban Construct & Digital City Teaching Expt Ctr, Sch Architecture & Planning, Kunming 650500, Peoples R China

[2] Shenzhen Inst Informat Technol, Inst Technol Marine Civil Engn, Shenzhen 518172, Peoples R China

[3] YCIH Green High Performance Concrete Co Ltd, Kunming 650500, Peoples R China

[4] UCL, Dept Civil Environm & Geomat Engn, London WC1E 6BT, England

来源：

CASE STUDIES IN CONSTRUCTION MATERIALS | 2024年 / 21卷

基金：

中国国家自然科学基金;

关键词：

PCE superplasticiser; Protein-based retarder; Surface coverage; Workability; Rheology; WATER FILM THICKNESS; YIELD-STRESS; CONCRETE; RHEOLOGY; HYDRATION; IMPACT; FLOWABILITY; PERFORMANCE; CHEMISTRY; PHASES;

D O I：

10.1016/j.cscm.2024.e03541

中图分类号：

TU [建筑科学];

学科分类号：

0813 ;

摘要：

The cementitious paste containing a high volume of calcined clay exhibits poor fluidity due to the thixotropic nature of the clay suspension. The study focuses on the impact of the stepwise addition of PCE and protein-based alkaline retarder (PAR) on the rheological properties of cement-calcined clay blends with varying calcined clay replacement levels. The addition sequences included prior addition (PA), simultaneous addition (SA), and delayed addition (DA) of PCE. The blends were evaluated based on their fluidity, rheology, and setting time. The results showed that the DA sequence notably improved the workability of the blends, minimizing the fluidity loss over 60 minutes and reduced the yield stress of the paste by up to 89.8 %. The adsorption of polymers on mineral particles was analyzed by total organic carbon (TOC), X-ray photoelectron spectroscopy (XPS), X-ray diffractometry (XRD) and Zeta potential test to reveal its mechanism. The results revealed a 17 % increase in polymer adsorption with the DA sequence, while the zeta potential of the blend experienced only a slight change. These findings suggest that the sequence of chemical admixture addition can significantly influence the working performance of cement-calcined clay blends. This provides new insights for improving the dispersion performance of these blends and promotes the application of limestone calcined clay cement.

引用

页数：18