Flexural behaviour of enhanced foamed concrete beams reinforced with GFRP bars

Tools

Alkurdi, N ORCID: https://orcid.org/0000-0001-6171-6887, 2021. Flexural behaviour of enhanced foamed concrete beams reinforced with GFRP bars. PhD, Nottingham Trent University.

Preview

Text
Nadir Alkurdi 2022.pdf - Published version
Download (11MB) | Preview

Abstract

Concrete is the second most widely consumed substance on earth after water. However, normal-weight concrete is a relatively heavy construction material with a density of 2400 kg/m3, which adds extra load on structures, resulting in larger foundations and structural elements section. The second issue is reinforcement corrosion, which has been one of the main durability problems in reinforced concrete. Therefore, there is a need for lightweight reinforced concrete that resists corrosion. This research aims to produce sustainable lightweight concrete reinforced with non-corrosive bars, which has the potential to be used in structural applications. The use of Foamed Concrete (FC) reinforced with Glass Fibre Reinforced Polymer (GFRP) bars in structural elements will reduce permanent actions on structures and foundations, contributes to more sustainable, energy-efficient construction and cost reduction by reducing structural elements size, labour and energy during transportation and construction stages, reinforcement corrosion repair and maintenance.

To investigate and develop the mechanical properties and structural behaviour of FC to be suitable for structural applications, 876 specimens classified into six different densities (800, 1000, 1200, 1400, 1600 and 1800 kg/m3) were tested. For each concrete density, four mixes were designed including the control mix and three different additives: metakaolin, silica fume and waste toner. The waste toner additive was collected from used printer cartridges. The experimental programme was considered to introduce a modified direct tensile test, where splitting and flexural tests were conducted to confirm its reliability. Full scale beams made of normal/ foamed concrete reinforced with steel/GFRP bars were tested experimentally, theoretically and numerically using Finite Element Modelling FEM.

The waste toner additive improved the FC mechanical properties by 30%. The bond between FC and GFRP bars was found to be 95% of normal weight concrete and steel bars. With the same total reinforcement amount of GFRP and steel bars, the ultimate flexural capacity of the GFRP reinforced foamed concrete beam was 87% of that in the steel-reinforced concrete beam, but the deflection and maximum crack width were larger than those of steel-reinforced concrete beams under the same service load levels. The results from FEM, showed good agreement with the experiment results. The theoretical equations developed in this study reasonably predicted the failure moments of the steel/GFRP reinforced. These results are promising and point to the significant potential of developing eco-friendly lightweight concrete reinforced with lightweight and anti-corrosive reinforcement bars.

Item Type:	Thesis
Creators:	Alkurdi, N.
Date:	July 2021
Divisions:	Schools > School of Architecture, Design and the Built Environment
Record created by:	Linda Sullivan
Date Added:	24 May 2022 15:13
Last Modified:	24 May 2022 15:13
URI:	https://irep.ntu.ac.uk/id/eprint/46364