Development of a low-cost cement free polymer concrete using industrial by-products and dune sand

Abstract

Abstract. Alkali-activated polymer concrete (APC) can potentially reduce CO2 emissions associated to concrete production by 84%. The binder in APC herein was synthesized using a combined sodium silicate-sodium hydroxide solution (i.e., alkali activator), alumino-silicate rich precursor (fly ash) and slag. Light weight expanded clay and desert dune sand were used as aggregates. An overview of an experimental program was presented, which involved evaluation of fresh and mechanical properties of the produced APC and counterpart mortar (APM). Variables investigated were the fly ash to slag ratio and curing conditions. The curing regimes adopted herein included 24 hours of curing at ambient conditions, 30oC, and 60 o C. The experimental program was undertaken in two stages, of these the first stage involved physical and chemical testing of constituent materials and the second stage involved testing or produced APM/APC. Reported were the setting times, workability, compression strength, strength development, flexural strength, tensile splitting strength, and plastic shrinkage strains. Relationship between strength results were investigated and effectiveness of codified predictive equations was evaluated.

Thermal and Structural Characterization of Geopolymer-Coated Polyurethane Foam—Phase Change Material Capsules/Geopolymer Concrete Composites

“…The impact of curing time from seven days to 28 days is increased compressive strength of 63.3% in the current study, while there are different findings reported in the literature. Gain in strength at the age of 28 days as compared to seven days is 14% higher [ 39 ], more than 1.5 times [ 51 ], 51.4% higher [ 52 ], and almost no change [ 53 ], while a few of the studies only investigated after seven days as they considered that most of the strength can be achieved after aging for seven days [ 54 , 55 ]. The international standard, ASTM C129-17 [ 56 ], requires nonloadbearing concrete units to achieve a compressive strength of 4.14 MPa.…”

Development of green cement mortar using industrial by-products

“…Therefore, the researchers and the construction industry are trying to recycle the industrial by-products and domestic wastes in the concrete industry as a partial replacement either for cement or aggregates [26][27][28][29]. For example, Ismail et al [30] used alkaline activated polymers concretes (APC) as an alternative to the ordinary concrete to reduce the harmful emissions from OPC. The mixture of the APC was made from fly ash, slag and Na2SiO3-NaOH solution (as an alkaline activator), and also clay and desert dune sands were added to the mixture as aggregates.…”