The geopolymer concrete (GC) is a cement replaced by aluminosilicate material combined with alkaline solution to produce strong binding property and replaced function of ordinary Portland cement. The purpose of this research was to determine the relationship between alkali solution concentrations (8 M, 10 M and 12 M), heat curing temperature and heat curing duration as the influencing parameters of concrete strengths. Geopolymer sample was prepared under different target heating temperatures which were room temperature and heat curing ranges of 60 °C to 100 °C for a duration curing period of 24 hours in the oven. Then the specimens were left in a room temperature until the testing day. The mechanical properties of geopolymer concrete were determined with the compressive test. The comparison was made with concrete control specimens that cured in ambient temperature. The results were determined from 7 days specimens after the curing process. The results show that the compressive strength of GCs under heat curing condition was developed quickly when there is an increase in temperature. It can be concluded that the temperature plays an important role in accelerating the GC strength increment compared to curing in ambient temperature.Â

Several researchers devoted considerable efforts to partially replace natural aggregates in concrete with recycled materials such as recycled tire rubber. However, this often led to a significant reduction in the compressive strength of rubberized concrete due to the weaker interfacial transition zone between the cementitious matrix and rubber particles and the softness of rubber granules. Thereafter, significant research has explored the effects of supplementary cementitious materials such as zeolite, fly ash, silica fume, and slag used as partial replacement for cement on rubberized concrete properties. In this study, systematic experimental work was carried out to assess the mechanical properties of palm oil fuel ash (POFA)-based concrete incorporating tire rubber aggregates (TRAs) using the response surface methodology (RSM). Based on the findings, reasonable compressive, flexure, and tensile strengths were recorded or up to 10% replacement of sand with recycled tire fibre and fine TRAs. In particular, the reduction in compressive, tensile, and flexural strengths of POFA concrete incorporating fibre rubber decreased by 16.3%, 9.8%, and 10.1% at 365 days compared to normal concrete without POFA and rubber. It can be concluded that utilization of a combination of POFA and fine or fibre rubber could act as a beneficial strategy to solve the weakness of current rubberized concrete’s strength as well as to tackle the environmental issues of the enormous stockpiles of waste tires worldwide.