Articles
  • The influence mechanism of modified calcium bentonite on drying shrinkage of alkali-activated material

  • Li Wanqianga,b, Jiang Chunmenga,b,* and Li Shuangxia,b

  • aCollege of Water Conservancy and Civil Engineering, Xinjiang Agricultural University, Urumqi 830052, PR China
    bXinjiang Key Laboratory of Hydraulic Engineering Security and Water Disasters Prevention, Urumqi 830052, PR China

  • This article is an open access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Volumetric instability is one of the main reasons restricting the engineering application of alkali-activated material (AAM). The aim of this work is to determine the most convenient calcination temperature of calcium bentonite (CB) to reduce the drying shrinkage of AAM. Five temperature gradients (20 ℃, 150 ℃, 600 ℃, 750 ℃, 900 ℃) and three admixture levels (5%, 10%, 15%) were considered. The results show that a calcination temperature of 150 °C and 15% admixture is the optimum treatment. The compressive strength of the AAM is improved, and the drying shrinkage is substantially reduced. The x-ray diffraction, scanning electron microscope, and mercury intrusion porosimetry tests have shown that calcination at 150 °C enhanced the interlayer properties for better performance than AAM prepared by dehydroxylation of CB calcined at high temperatures. The water retention reduces the evaporation of water and generates N-A-S-H gels after dissolution. Causes coarsening of the pore size of the AAM and reduced drying shrinkage


Keywords: Alkali-activated, Calcium bentonite, Drying shrinkage, Pore structure

This Article

  • 2023; 24(2): 329-335

    Published on Apr 30, 2023

  • 10.36410/jcpr.2023.24.2.329
  • Received on Oct 11, 2022
  • Revised on Dec 16, 2022
  • Accepted on Dec 31, 2022

Correspondence to

  • Jiang Chunmeng

  • aCollege of Water Conservancy and Civil Engineering, Xinjiang Agricultural University, Urumqi 830052, PR China
    bXinjiang Key Laboratory of Hydraulic Engineering Security and Water Disasters Prevention, Urumqi 830052, PR China
    Tel : +86-13209901058

  • E-mail: jiangcm93@163.com