Size effect and age factor in mechanical properties of BST Light Weight Concrete. (20th July 2018)

• Record Type: Journal Article
• Authors: Vakhshouri, Behnam; Nejadi, Shami
• Is Part Of: Construction & building materials. Volume 177(2018)
• Page Start: 63
• Page End: 71
• Publication Date: 2018-07-20
• Subjects: BST Commercial name of EPS-LWC -- CYL Cylinder -- CS Compressive Strength -- EPS Expanded Poly-Styrene -- GP General Purpose -- KN Kilo Newton -- LWC Light-Weight Concrete -- MM millimeter -- ML milliliter -- MoE Modulus of Elasticity -- MPa Mega Pascal -- STS Splitting Tensile Strength -- SSD Saturated Surface-Dry -- SL Shrinkage Limited -- g/m3 gram per cubic meter -- kg/m3 Kilogram per cubic meter -- t/m3 ton per cubic meter -- m2/kg Squared meter per Kilogram -- µm micrometer -- µε micro strain -- °C degree Celsius -- fcmy′(d) Compressive strength of cylinder (function of d) -- fctmu(d) is the tensile strength of the cylinder with any size as function of the diameter d -- fc′ Compressive strength of the concrete at the age of 28 days -- fcmu′ Compressive strength of the concrete at different ages -- fct Tensile strength of concrete -- fcmy′(d) Compressive strength of concrete for cube or cylinder -- d characteristic specimen dimension (diameter of cylinder or cube dimension) -- dmax maximum size of the coarse aggregate -- l0 = 2.0dmax is the characteristic length of test specimen -- σ0 = α ×fc′ characteristic strength at failure -- σN nominal strength at failure -- σcub compressive strength for cube -- ρc density of concrete (kg/m3) -- ρ0 nominal density of conventional concrete = 2300 kg/m3 n1= aspect ratio of test specimen -- A1, B, B1, X2, X4, α, β, γ, δ, η, λ0, λ, empirical coefficients; Expanded polystyrene bead -- Light Weight Concrete -- Compressive strength -- Splitting tensile strength -- Size and shape effect -- Age factor; Building materials -- Periodicals; 624.18
• DOI: 10.1016/j.conbuildmat.2018.05.115
• Languages: English
• ISSNs: 0950-0618

Abstract

Highlights: Fracture mechanics is the basic principle in studying the size effect. Size effect (scaling factor) and shape effect are not investigated in EPS-LWC. Different shape and size of test specimens are used in this study. Experimental values of compressive and splitting tensile strength are evaluated. Existing models of size effect of LWC conventional concrete are investigated. Age factor in compressive and splitting tensile strength of EPS-LWC are proposed. Effect of shape and size of test specimens on EPS-LWC properties are modeled. Abstract: Replacement of whole or part of normal aggregates with Expanded Polystyrene (EPS) beads in the concrete mix is a reliable method to produce Light Weight Concrete (LWC) with considerable advantages. Due to modification effect on mechanical properties of LWC, it is important to examine whether all the assumed hypotheses about conventional concrete also are applicable for LWC structures. Based on an experimental program, this study investigates the effects of specimen size and shape on the compressive and tensile strength of this type of LWC. In this regard, cylinder specimens with 75 × 150, 100 × 200 and 150 × 300 mm dimensions and cube specimens with 100 and 150 mm dimensions were cast and cured in laboratory conditions. Compressive and tensile strengths were tested after 3, 7, 14, 21, 28, 56 and 91 days. The correlation factor between the compressive strength, tensile strength and the shape and size of specimens is evaluated also.