Mechanical Properties of Macro Polypropylene Fibre-Reinforced Concrete

Abstract

Adding fibers to concrete helps enhance its tensile strength and ductility. Synthetic fibres are preferable to steel ones which suffer from corrosion that reduces their functionality with time. More consideration is given to synthetic fibres as they can be sourced from waste plastics and their incorporation in concrete is considered a new recycling pathway. Thus, this work investigates the potential engineering benefits of a pioneering application using extruded macro polyfibres in concrete. Two different fiber dosages, 4 kg/m3 and 6 kg/m3, were used to investigate their influence based on several physical, mechanical and microstructural tests, including workability, compressive strength, modulus of elasticity, splitting-tensile strength, flexural test, CMOD, pull-out test and porosity. The test results revealed a slight decrease in the workability of the fibre-reinforced concrete, while all the mechanical and microstructural properties were enhanced significantly. It was observed that the compressive, splitting tensile and bonding strength of the concrete with 6 kg/m3 fibre dosage increased by 19.4%, 41.9% and 17.8% compared to the plain concrete specimens, respectively. Although there was no impact of the fibres on the modulus of rupture, they significantly increased the toughness, resulting in a progressive type of failure instead of the sudden and brittle type. Moreover, the macroporosity was reduced by the fibre addition, thus increasing the concrete compressive strength. Finally, simplified empirical formulas were developed to predict the mechanical properties of the concrete with fibre addition. The outcome of this study will help to increase the implementation of the recycled plastic waste in concrete mix design and promote a circular economy in the waste industry.

Glass Fibers Reinforced Concrete: Overview on Mechanical, Durability and Microstructure Analysis

“…The optimal glass fiber inclusion level is 1.5 percent, with 14.29, 8.12, and 10.03 percent increases in compressive, flexural, and split tensile strengths, respectively [ 65 ]. Macro poly fibers are a kind of macro synthetic polypropylene fiber (PP) created and produced in a new continuously deformed shape for excellent performance and optimal anchoring to concrete, making them more structurally compliant [ 66 ]. The drying shrinkage of multi-filament and fibrillated fibrous concrete was reduced by 40% compared to standard concrete; this decrease is due to the greater tensile strength of synthetic fibers, which helps bear additional loads.…”

Flexural Behavior of High Strength RC Beams Incorporating Nano-Silica and Macro-Polypropylene Fiber

“…The maximum flexural strength obtained among mixes was 7.91 MPa at age 28 days and 7.94 MPa at age 56 days for that mix containing the combination of 3% of NS and 0.5% of MPF (B4-NS 3%-MPF 0.5%) compared to the control mix increased by 27.8% and 28.3%, respectively. It is obvious that the fibers significantly affect flexural strength and prevent quick cracking in plain concrete (Abousnina et al, 2021). Flexural strength in the concrete mix increased slightly when NS was used alone when compared to the control mix; this may be due to an increase in compressive strength.…”

“…Nevertheless, glass fibers are extremely strong but have a low alkali resistance, particularly when added to concrete. Recently, synthetic fibers are attracting focus from researchers due to their greater environmental sustainability than other types of fibers (Abousnina et al, 2021).…”

“…It is primarily used in concrete structures to strengthen them and minimize shrinkage cracking to a limited extent (Lee et al, 2016;Yazdanbakhsh et al, 2015). As a consequence, many research studies have been carried out on fiber (Abousnina et al, 2021;Ahmed et al, 2006;Bagherzadeh et al, 2012;Fallah & Nematzadeh, 2017;Lee et al, 2016;Mashrei et al, 2018;Mtasher et al, 2011;RAS, 2006). However, very few studies have been focused on the Nano-materials and MPF together.…”

Advances on concrete strength properties after adding polypropylene fibers from health personal protective equipment (PPE) of COVID-19: Implication on waste management and sustainable environment

“… Abousnina et al (2021) , study the impact of macro polyfibers on the mood of filler which was modified from longitudinal splitting to shear failure. Additionally, compared to plain concrete, the addition of the 4 kg/m3 and 6 kg/m3 fiber dosages increased compressive strength by 9.6% and 19.4%, respectively.…”