Mechanical behaviour at high temperature of alkali-activated aluminosilicates (geopolymers)

摘要: Abstract This study was designed to determine the effect of temperature on mechanical strength (in both in vivo and post-exposure trials) two alkaline cements (without OPC): (a) 100% fly ash (FA) (b) 85% FA + 15% bauxite, activated solution used 10-M NaOH + 15% sodium silicate. A Type I 42.5 R Portland cement as a control. Two series trials were conducted: (i) which bending compressive strength, fracture toughness modulus elasticity determined at different temperatures; (ii) post-firing trials, assessing residual after 1-h exposure high temperatures subsequent cooling. The findings showed that from 25 600 °C, irrespective type test or post-firing), rose, with specimens exhibiting elastic behaviour consequently brittle failure. At over differed depending test: induced pseudo-plastic strain decline did not necessarily entail specimen failure; rose.