Flexural behaviour of pumice lightweight concrete reinforced with end-hooked steel fibres
Konstantinos Christidis, Efstratios Badogiannis, Christina Mintzoli
Abstract
A study on the mechanical properties of end-hooked steel-fibre reinforced pumice lightweight concrete is presented. Typical compression and three-point bending tests were performed in a reference lightweight concrete batch, where two different steel end-hooked fibres were added in four different contents 0.5%, 0.75%, 1.0%, and 1.5% per volume. The experimental results were evaluated in both strength and deformation terms and further processed, in order to illustrate the influence of fibres to the strength and deformation capacity, in correlation to the geometrical aspect ratio and the volume fraction of the fibres. Compressive strength, but mainly flexural strength was found to be significantly enhanced, especially, in terms of post crack behaviour. An effort to model the post-crack behaviour in flexure was also conducted. A multi-phase constitutive law is proposed which describes the Stress - Crack Mouth Opening Displacement behaviour of steel-fibre reinforced pumice lightweight concrete in correlation to the mechanical properties of plain lightweight concrete.