Structural and durability properties for magnesia alumina silicate concrete. (18th July 2022)

• Record Type: Journal Article
• Authors: Dhakal, Milap; Scott, Allan N.; Dhakal, Rajesh P.; Clucas, Don
• Is Part Of: Construction & building materials. Volume 340(2022)
• Publication Date: 2022-07-18
• Subjects: Ec Young's modulus of elasticity of concrete -- Eit Initial slope of ε-σ curve -- fc concrete compressive strength -- fcr modulus of rupture -- k material constant of cement paste -- k1 and k2 modification factors used in ε-σc correlations -- M-(A)S-H Magnesium alumino silicate hydrate -- M−S−H Magnesium silicate hydrate -- P porosity of cement paste at any time -- P' porosity of concrete or mortar at any time -- Po initial porosity of cement paste -- R2 coefficient of determination of regression model -- S seconds -- s rebar slip -- su rebar bond slip at ultimate bond stress -- T50 time required for the slump flow to reach the spread diameter of 500 mm or 50 cm -- w/c ratio of mass of water to mass of cement -- w/cm ratio of mass of water to mass total cementitious materials -- α porosity modification factor for cement mortar or concrete -- β Regression coefficient = -- ε axial or longitudinal strain -- κ permeability coefficient -- μ Poisson's ratio -- σc concrete compressive stress -- σs splitting tensile strength of concrete -- ρ density of concrete -- ρc density of cement -- τ concrete-rebar bond stress -- τm average concrete-rebar bond stress -- τu ultimate concrete-rebar bond stress -- τ0.1 concrete-rebar bond stress at rebar slip of 0.1 mm -- ϕ rebar diameter; M−S−H concrete -- Mechanical properties -- Medium-strength SCC -- Models of M−S−H concrete properties -- Bond performance of M−S−H concrete -- Durability properties; Building materials -- Periodicals; 624.18
• DOI: 10.1016/j.conbuildmat.2022.127725
• Languages: English
• ISSNs: 0950-0618

Abstract

Highlights : MgO-Al2 SiO3 cement concrete can be designed and constructed similar to conventional PC concrete. Structural and durability properties of MgO-Al2 SiO3 cement concrete are similar to those of PC concrete. MgO-Al2 SiO3 demonstrated better transfer of tensile stresses allowing for greater tensile strain. The rebar-concrete bond performance in the MgO- Al2 SiO3 concrete is comparable to that of PC concrete. Abstract: This paper reports on the fresh, structural and durability properties of a Magnesia-Metakaolin (MgO-Mk) based concrete compared with a conventional Portland cement (PC) concrete. Metakaolin, representing the family of aluminosilicate (Al2 SiO3 ) including low-kaolinitic clays, provides a viable option for use in the M−S−H and M−A−S−H binder system. Two representative cementitious formulations of MgO-Mk cement at a single MgO/clay mass ratio with 100% and 70% Al2 SiO3 content were used in the study. In addition to the basic properties of concrete such as strength and density, this paper also presents the result of comprehensive tests undertaken to evaluate the elastic properties and bond performance of the M−S−H concrete using both steel and basalt reinforcing. The results of the current study demonstrate the properties of MgO-Mk-based M−S−H concrete to be comparable with, if not superior to, those of its PC counterpart.