Production of lightweight geopolymer concrete

Abstract

Lightweight concrete has been known all around the world for decades. As a masonry material, there is an advantage: it has sufficient mechanical strength despite of its light weight. This research focuses on the production of recycled concrete based lightweight geopolymer concrete samples using glass foam aggregates. During the research geopolymer and concrete samples were made and finally their properties were investigated and compared. In the research work an alkaline silicate reaction (ASR) was also studied on the glass foam lightweight aggregates, which is very important for concrete failure. Material structural and morphological tests were obtained by scanning electron microscopy (SEM) to characterize the geopolymer concrete samples. Compressive strength of lightweight concrete and lightweight geopolymer was determined at the age of 7 days. Glass foam is suitable for use as a lightweight aggregates for workability. Based on the 7 days compressive strength results no crust typical of the ASR reaction was detected on the surface of the mixtures.

A Review of Lightweight Geopolymer Concrete Based on Slag

“…A study comparing the properties of geopolymer concrete Construction and Demolition Waste Recycling aggregate with those of the aggregate from volcanic pumice was reported. The lightweight geopolymer concretes containing RCB and pumice aggregate exhibited lower mechanical properties compared with those of geopolymer concrete with crushed limestone (natural aggregate), which was as expected [13]. However, they had better thermal insulation and higher residual strength after exposure to temperatures of 400-800°C.…”

“…The author concludes that metakaolin blends have good workability and hardening properties. Rovnanik et al, 13 show that to attain early gain of compressive and flexural strength, Higher temperature curing has to be done. On the contrary, this had an adverse effect on larger pore size and decrease in 28-day strength when compared to that of ambient curing condition.…”

“…This is due to leaching of alkaline solution at the early stages, this leads to a decrease in pH, hindering hydration, and less strength gain. Rovnaník (2010) 13 The mechanical properties were investigated on the basis of pore distribution analysis. This has been evaluated by means of mercury intrusion porosimetry analysis that was conducted on paste samples using Micromeritics pore size 9300 porosimeter.…”