Please use this identifier to cite or link to this item: http://hdl.handle.net/10397/76021
Title: Using incinerated sewage sludge ash to improve the water resistance of magnesium oxychloride cement (MOC)
Authors: He, PP 
Poon, CS 
Tsang, DCW 
Keywords: Magnesium oxychloride cement
Incinerated sewage sludge ash
Microstructure
Gel formation
Water resistance
Issue Date: 2017
Publisher: Elsevier
Source: Construction and building materials, 2017, v. 147, p. 519-524 How to cite?
Journal: Construction and building materials 
Abstract: This paper presents an experimental investigation on the water resistance of magnesium oxychloride cement (MOC) incorporating incinerated sewage sludge ash (ISSA). Cement pastes were prepared to evaluate the compressive strength and microstructure of the blended cements. Besides, the volume stability of cement mixture during air curing and water immersion was tested by measuring the length change of mortar bar specimens. In addition to cement paste and mortar, Na2SiO3 center dot 9H(2)O and Al(NO3)(3)center dot 9H(2)O were used to react with MOC as the replacement of ISSA to synthesize pure hydration products. Paste studies revealed that ISSA additions of 10-30% significantly improve the water resistance of MOC. Mortar studies showed that ISSA significantly reduced expansion of mortar bars immersed in water. The improved water resistance and reduced expansion is directly related to the decrease in MgO content of pastes and an improved stability of Phase 3 (3Mg(OH)(2)center dot MgCl2 center dot 8H(2)O) and Phase 5 (5Mg(OH)(2)center dot MgCl2 center dot 8H(2)O) in water. Results from sol-gel experiments suggest that ISSA can act as a source of soluble Al and Si which results in the formation of an amorphous M-Cl-A-S-H type cementitious gel. The gel formed could help improve Phase 3 and Phase 5 stability in water by interlocking mechanisms which impede the access of water to Phase 3 and Phase 5.
URI: http://hdl.handle.net/10397/76021
ISSN: 0950-0618
EISSN: 1879-0526
DOI: 10.1016/j.conbuildmat.2017.04.187
Appears in Collections:Journal/Magazine Article

Access
View full-text via PolyU eLinks SFX Query
Show full item record

SCOPUSTM   
Citations

4
Citations as of May 11, 2018

WEB OF SCIENCETM
Citations

3
Last Week
0
Last month
Citations as of May 20, 2018

Google ScholarTM

Check

Altmetric


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.