Study of Modulus of Rupture on Geopolymer Concrete Temperature Difference Methods of Steam Curing

Abstract

Geopolymer concrete is concrete without cement. Cement replacement due to cement production has resulted in a global warming effect. Fly ash as a substitute for cement is a waste of coal production containing pozzolan properties. Concrete must have reliable mechanical properties of the modulus of rupture. This research aims to study the influence of the modulus of rupture on the steam curing of geopolymer concrete-based fly ash as a substitute for cement and alkaline activator of 12 Mol NaOH: Na2SiO3 (3:1). The applied steam curing temperatures are 60oC, 70oC, and 80oC. After steam curing, the sample is stored at ambient curing and submerged in water. The sample beam is 15 x 15 cm x 60 cm to find the value of the modulus of rupture. The test results obtained a modulus of rupture concrete geopolymer steam curing temperature of 80 and ambient curing of 3.87 MPa. Steam curing of 70oC and ambient curing of 3,71 MPa. Steam curing of 60oC and the ambient curing is 2.71MPa. It can be concluded that the higher the steam curing temperature the value of the modulus of rupture is higher.