Alkali-activated concrete: Engineering properties and stress–strain behavior

Abstract

h i g h l i g h t sThe engineering properties of alkali-activated concretes (AAC) are determined.Results are compared to existing models for portland cement concrete (PCC). Models are proposed to predict tensile strength and modulus of AAC. AAC exhibits higher tensile strength and lower Poisson's ratio than PCC. Alkali-activated slag concrete is much more brittle than PCC. a b s t r a c tThis paper presents an investigation into the tensile strength, modulus of elasticity, Poisson's ratio, and stress-strain relationships of alkali-activated portland-cement-free concrete made with fly ash or ground granulated blast furnace slag (GGBFS) as the sole binder. Alkali-activated concrete is shown to be stronger in tension and have lower Poisson's ratio than portland cement concrete. Relationships are proposed to estimate the tensile strength and modulus of elasticity based on the compressive strength of alkali-activated concrete, which are of the same form as those currently employed for portland cement concrete.

Establishment of a preconditioning regime for air permeability and sorptivity of alkali-activated slag concrete

“…Encouragingly, previous research [5][6][7][8][9] confirms that alkali-activated slag concrete (AASC) offers a range of performance benefits, such as high mechanical strength at early stages of curing, excellent acid-resistant characteristics, good resistance to freeze-thaw cycles and resistance to elevated temperatures. As such, the production and performance of AASC have been a highly active area of academic and industrial research over the past decades.…”

Long-term durability of rock-based geopolymers aged at downhole conditions for oil well cementing operations

“…This supports the findings of other studies which also found lower tensile strengths for geopolymers compared to Portland cement. [28,29] Some studies however have suggested improved tensile strength compared to Portland cement. [30] The tensile strength of the specimens exposed to crude oil showed a steady value at the time intervals.…”

Structural concrete based on alkali‐activated binders: Terminology, reaction mechanisms, mix designs and performance

“…Analogous to current concrete standards, the mechanical properties of AACs can be expressed as a function of the compressive strength by means of empirical models. In the case of the flexural and/or tensile strength, initial results by the authors show that the 28‐day tensile strength of AACs exceeds the predictions given in EN 1992:2011, demonstrating an increased tensile resistance …”