Coupling effect assessment of vacuum based pozzolana slurry encrusted recycled aggregate and basalt fiber on mechanical performance of fiber reinforced concrete. (20th September 2021)

• Record Type: Journal Article
• Authors: Ahmed, Wisal; Lim, C.W.
• Is Part Of: Construction & building materials. Volume 300(2021)
• Publication Date: 2021-09-20
• Subjects: BF basalt fiber -- C&D construction and demolition -- CH calcium hydroxide -- CSH calcium silicate hydrates -- ESEM environmental scanning electron microscope -- FA fly ash -- FRAC fiber reinforced recycled aggregate concrete -- GPa gigapascal -- ITZ interfacial transition zone -- kPa kilopascal -- MPa megapascal -- NAC normal aggregate concrete -- NCA normal concrete aggregate -- NFA natural fine aggregate -- NSC normal strength concrete -- OPC ordinary Portland cement -- PCE polycarboxylic-ether -- RAC recycled aggregate concrete -- RCA recycled concrete aggregate -- RS reference specimen -- SF silica fume -- SP superplasticizer -- TRCA treated recycled concrete aggregate -- UPV ultra-sonic pulse velocity -- UTM universal testing machine -- XRD x-ray diffraction -- 20RAC-0BF RAC prepared with 20% RCA and 0% BF -- 20TRAC-0BF RAC prepared with 20% treated RCA and 0% BF -- 20TRAC-1BF RAC prepared with 20% treated RCA and 1% BF -- ƒʹCS compressive strength -- ƒʹFS flexural strength -- ƒʹST splitting tensile strength; Adhered mortar -- Basalt fiber -- Green recycled concrete -- Mechanical properties -- Pozzolana slurry; Building materials -- Periodicals; 624.18
• DOI: 10.1016/j.conbuildmat.2021.124032
• Languages: English
• ISSNs: 0950-0618

Abstract

Graphical abstract: Highlights: An effective method for improving adhered mortar to the surface of RCA. Microstructural deficiencies in the RAC matrix were successfully counteracted. BF reinforced TRAC displayed significant improvement in the mechanical properties. RAC modified with proposed technique can be utilized in structural applications. Abstract: To deal with the rapidly increasing construction and demolition (C&D) waste, the use of eco-friendly and resource efficient concrete in structural applications has become greatly essential for the modern-day construction industry that emphasizes on green environment and sustainability. In this regard, the applications of recycled concrete aggregate (RCA) in place of virgin aggregate can be of great profitable use however, its inferior quality and lower mechanical properties are the major challenges which limit their practical adaptation. To augment the mechanical performance of RAC and promote its structural applications, we applied a new eco-friendly and effective strength-enhancing technique that involves synergistic use of vacuum-based encrusted RCA and fiber reinforcing technique. The performance of this new technique is assessed for two types of RAC containing 20% and 100% of pozzolana slurry treated RCA and reinforced with 0%, 0.25%, 0.5%, and 1% volume fractions of basalt fiber (BF) with regards to various physical and mechanical properties. The compressive loading capacity, splitting tensile strength and flexural strength of BF reinforced 20TRAC formulation reveal maximum improvement of 16%, 24% and 57%, respectively, while that of BF reinforced 100TRAC formulation show maximum enhancement of 8%, 18% and 37%, respectively. Furthermore, the microstructure study revealed improved concrete matrix quality and excellent bonding between BF and host concrete matrix. The ultrasonic pulse velocity and water absorption increased with increase in the BF dosage. Lastly, the correlation analysis for various physical and mechanical properties is presented that depicts an excellent relationship with a correlation factor of greater than 0.9. Conclusively, the composite addition of vacuum-based pozzolana slurry treated RCA and BF constitutes better microstructure and thereby is able to upgrade the mechanical performance of fiber reinforced recycled concrete.