Creep Behaviour of Fly Ash-Based Geopolymer Concrete

Abstract

Fly ash-based geopolymer concrete is manufactured using fly ash as its source material and does not use Portland cement at all. Beside fly ash, alkaline solution is also utilized to make geopolymer paste which binds the aggregates to form geopolymer concrete. This paper presents the study of creep behaviour of fly ash-based geopolymer concrete. Four series of specimens with various compressive strengths were prepared to study its creep behaviour for the duration of test up to one year. The test method followed the procedures applied for Ordinary Portland Cement (OPC) concrete. Test results show that fly ash-based geopolymer concrete undergoes low creep which is generally less than that of OPC concrete. After one year of loading, the results for specific creep of fly ash-based geopolymer concrete in this study ranges from 15 to 29 microstrain for concrete compressive strength 67-40 MPa respectively. From the test results, it is also found out that the creep coefficient of fly ash-based geopolymer concrete is about half of that predicted using Gilbert's Method for OPC concrete.

Methodology for Assessing Long-Term Deformation Influence on Geopolymer Composite Microstructure

“…In general, the fly ash-based GP composite would have a lower creep than OPC based concrete. It has been claimed that GP concrete cured at 60 °C for 24 hours has up to 50 % less compressive creep than OPC based concrete [22]. Similar creep properties have been observed for the specimens cured for 6 hours at 60 °C [101].…”

“…In Paper IV [49], recycled tyre cord reinforcement decreases creep strains by 30 %. It has been claimed [22] that this low creep is attributed to a micro aggregation effect of unreacted fly ash in the binder.…”

Selection of an Effective Activating Agent for Coke Production Waste

“…Therefore, the author proposed quartz dust as an additional source of silica and aluminum oxide. The use of quartz sand/dust, fly ash is also mentioned in the literature on geopolymer synthesis [10][11][12][13].…”

Nghiên cứu biến dạng co ngót và thời điểm xuất hiện vết nứt do co ngót của bê tông bằng phương pháp vòng kiềm chế

“…Tuy nhiên, chỉ có một vài nghiên cứu về vấn đề co ngót khô và tính chất từ biến của GPC sử dụng tro bay và xỉ lò cao. Nghiên cứu của Wallah và Rangan [5,6] đã chỉ ra rằng GPC sử dụng tro bay, được dưỡng hộ nhiệt, có từ biến nhỏ, chỉ khoảng 50% so với từ biến của bê tông thường được tính toán dự báo theo tiêu chuẩn Úc AS3600-2009 [7]. Mẫu bê tông được dưỡng hộ nhiệt ở nhiệt độ 60 °C trong 24h.…”