eprintid: 10192954
rev_number: 7
eprint_status: archive
userid: 699
dir: disk0/10/19/29/54
datestamp: 2024-06-03 12:45:18
lastmod: 2024-06-03 12:45:18
status_changed: 2024-06-03 12:45:18
type: article
metadata_visibility: show
sword_depositor: 699
creators_name: Gurbuz, Ezgi
creators_name: Erdem, Savas
creators_name: Zhang, Mingzhong
title: Static and impact performance of engineered cementitious composites with hybrid graphite nano platelets modified PVA and shape memory alloy fibres
ispublished: pub
divisions: UCL
divisions: B04
divisions: C05
divisions: F44
keywords: Strain-hardening cementitious composites, Surface treatment, Shape memory alloy,
Graphite nano platelets, Dynamic properties
note: This version is the author accepted manuscript. For information on re-use, please refer to the publisher’s terms and conditions.
abstract: Polyvinyl alcohol (PVA) fibre has been widely adopted to produce engineered cementitious composites (ECC), the overall performance of which is highly dependent on the fibre surface characteristics. The traditional approach to improve PVA fibre bridging ability is to tailor the surrounding matrix properties. However, this common practice need to do a lot of laborious experimental works, and thus it has limited efficiency and practicality. Therefore, special surface treatments on PVA fibres are required to create synergistic interactions between fibre and surrounding matrix to retain excellent tensile ductility and better mechanical performance. This paper proposes a novel treatment method for PVA fibres using nano graphite platelets to modify the PVA fibre surface and improve the mechanical properties of PVA fibre reinforced ECC. To evaluate the effectiveness of such treatment, a systematic experimental study was performed. Firstly, static contact angle measurements, scanning electron microscopy and atomic force microscopy were employed to monitor the wettability and physical changes on the fibre surface. Then, the static and dynamic mechanical properties as well as microstructural characteristics of ECC with hybrid modified PVA fibres (2 vol%) and shape memory alloy (SMA) fibres (0.25 vol%, 0.50 vol% and 1 vol%) were examined. The results indicate that the graphite nanoplatelets treated PVA fibres (GPVA) exhibit high hydrophobicity and surface roughness providing steady-state crack propagation, which is a necessary condition to ensure multiple cracking and improving the higher fibre bridging complementary energy. This is evidenced by significantly densified the transition zone between the graphite treated PVA fibres and the matrix, and improved the flexural tensile strength and the toughness. The calculated surface roughness of 28.86 μm and lots of peaks and valleys on the 3D topographical micrographs of the cracking faces confirmed that 1 SMA-2 GPVA specimen efficiently participated in transferring stress through the composite, leading to a greater vertical impact reaction force. Finally, the structure-property relation for flexural versus fracture behaviour and the effectiveness of SMA fibres on the crack-healing feature of the composites were studied by using digitized fractal analysis and through the heat treatment. The disseminated fracture energy (Ws/Gf) value reached 130 and the crack sizes the crack size decreased by 34 %, which were much better than that of the reference composites. The nano treatment of PVA fibres in ECC provides an innovative and sustainable solution for engineering structures with requirement of high tensile ductility and high impact resistance, e.g., military infrastructure and industrial floors.
date: 2024-09-01
date_type: published
publisher: Elsevier BV
official_url: http://dx.doi.org/10.1016/j.jobe.2024.109776
full_text_type: other
language: eng
verified: verified_manual
elements_id: 2279925
doi: 10.1016/j.jobe.2024.109776
lyricists_name: Zhang, Mingzhong
lyricists_id: MZHAA72
actors_name: Zhang, Mingzhong
actors_id: MZHAA72
actors_role: owner
full_text_status: restricted
publication: Journal of Building Engineering
volume: 92
article_number: 109776
issn: 2352-7102
citation:        Gurbuz, Ezgi;    Erdem, Savas;    Zhang, Mingzhong;      (2024)    Static and impact performance of engineered cementitious composites with hybrid graphite nano platelets modified PVA and shape memory alloy fibres.                   Journal of Building Engineering , 92     , Article 109776.  10.1016/j.jobe.2024.109776 <https://doi.org/10.1016/j.jobe.2024.109776>.      
 
document_url: https://discovery.ucl.ac.uk/id/eprint/10192954/1/Accepted%20Version.pdf