期刊
CONSTRUCTION AND BUILDING MATERIALS
卷 69, 期 -, 页码 285-294出版社
ELSEVIER SCI LTD
DOI: 10.1016/j.conbuildmat.2014.07.018
关键词
Geopolymer; Strength; Microstructure; Subgrade; Fly ash; Calcium carbide residue
资金
- Thailand Research Fund under the TRF Senior Research Scholar program Grant [RTA5680002]
- Suranaree University of Technology under SUT-Ph.D. program
- Higher Education Research Promotion and National Research University Project of Thailand, Office of Higher Education Commission
Calcium Carbide Residue (CCR) and Fly Ash (FA) are waste by-products from acetylene gas and power plant production, respectively. The liquid alkaline activator studied in this research is a mixture of sodium silicate solution (Na2SiO3), water and CCR. The primary aim of this research is to investigate the viability of using CCR, a cementitious waste material, as an alkaline activator and FA as a precursor to improve the engineering properties of a problematic silty clay to facilitate its usage as stabilized subgrade material. The influential factors studied are Na2SiO3/water ratio, FA replacement ratio, curing time, curing temperature and soaking condition for a fixed CCR content of 7%. Strength development is investigated via the unconfined compression test. Scanning Electron Microscopy (SEM) observation is used to explain the role and contribution of influential factors on strength development. CCR dissolves the silicon and aluminum in amorphous phase of FA and the Na2SiO3 acts as a binder. The maximum soaked strength of the clay-FA geopolymer is found at Na2SiO3/water ratio of 0.6 and FA replacement ratio of 15%. The optimal Na2SiO3/water ratio is approximated from index test, which is a very practical approach. The clay-FA geopolymers with 40 degrees C curing exhibit higher strength than those with room temperature curing, indicating the possibility of using clay-FA geopolymer for pavement subgrade applications. The 7-day soaked strength at the optimal ingredient meets the strength requirement for subgrade materials specified by the local national road authority. CCR is found to be a sustainable alkaline activator for geopolymer stabilized subgrade materials, which will result in the diversion of significant quantities of this by-product from landfills. (C) 2014 Elsevier Ltd. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据