Fly-ash-based geopolymer composites incorporating cold-bonded lightweight fly ash aggregates

Küçük Resim Yok

Tarih

2021

Dergi Başlığı

Dergi ISSN

Cilt Başlığı

Yayıncı

Elsevier Sci Ltd

Erişim Hakkı

info:eu-repo/semantics/closedAccess

Özet

In this study, effects of cold-bonded lightweight fine aggregate (LWFA) on the geopolymer composites (GCs) were investigated in terms of fresh, physical, mechanical and durability properties. LWFA and different diameters quartz aggregates were used in the production of fly-ash-based GCs. However, LWFA was only replaced with the quartz aggregate of 1.2-2.5 mm. A mixture of 12 M NaOH and Na2SiO3 solution was prepared as 1/2.5. Unit weight, specific gravity, water absorption, apparent porosity, compressive and flexural strengths, ultrasonic pulse velocity and water sorptivity coefficient of GCs were determined. According to the test results, workability of GCs improved as the usage rate of LWFA increased. Due to the surface characteristics of LWFA, the mechanical properties of GC were enhanced by the geopolymerization reaction conducted between LWFA with alkali activators. Thus, the compressive strength of GC with 25% LWFA was 39.6% higher than that of the control GC at 28th day. This conclusion supported by TGA/DTA and FTIR analysis indicated that N-A-S-H gel of GC incorporating 25% LWFA was higher compared to control mixture. Also, GCs incorporating 40% and higher LWFA showed lower performance than control GC. (C) 2020 Elsevier Ltd. All rights reserved.

Açıklama

Anahtar Kelimeler

Geopolymer composite, Microstructural analyses, Strength and Durability, Physical properties, LWFAs

Kaynak

Construction and Building Materials

WoS Q Değeri

Q1

Scopus Q Değeri

Q1

Cilt

272

Sayı

Künye