Trabacchin, Giulia;
(2022)
Bond of Basalt Fibre Reinforced Polymer Bars to Geopolymer Concrete.
Doctoral thesis (Ph.D), UCL (University College London).
Preview |
Text
GiuliaTrabacchin_PhDThesis.pdf - Accepted Version Download (6MB) | Preview |
Abstract
Geopolymer concrete (GPC), manufactured with industrial by-products (e.g. fly ash and slag) activated by alkaline solutions, has been considered as a promising alternative to Portland cement concrete because of its superior engineering properties and sustainable features (e.g. low CO2 emissions and reuse of industrial wastes). Basalt fibre reinforced polymer (BFRP) bars have been recently introduced to replace steel reinforcement owing to their light weight, excellent mechanical properties, and high corrosion resistance. The studies on the structural performance of GPC reinforced with BFRP bars have proved its suitability as a substitute for conventional reinforced concrete, while the bond between GPC and BFRP bars which plays a critical role in structural performance and design has not been explored to date. This thesis aims to investigate experimentally, numerically and theoretically the bond of BFRP bars to GPC. Pull-out tests were conducted to study the bond behaviour of BFRP bars in GPC in terms of bond stress-slip response, bond strength, and failure mechanisms and estimate the effects of different factors including bar diameter, embedment length, bar surface and compressive strength of concrete. Afterwards, 3D finite element modelling of pull-out process using concrete damage plasticity model for GPC and cohesive zone model for BFRP bar-GPC interface was carried out to gain insight into the stress distribution along the bar and failure mechanisms. Furthermore, a theoretical bilinear bond stress-slip model validated with experimental data was proposed to analytically describe the bond between BFRP bars and GPC. Finally, a parametric study was performed to estimate the effects of different factors on the bond behaviour of BFRP bars in GPC, based on which a formula for predicting the bond strength was developed and compared with experimental data and recommendations from existing standard codes for FRP reinforced concrete. This research provides an in-depth understanding of the interactions between BFRP bars and GPC. The experimental results show that the bond stress-slip curve of BFRP bars to GPC was bilinear, with three characteristic stages (ascending, peak and descending). The bond was mainly offered by mechanical interlocking of the bar ribs against the concrete lugs. The FE and theoretical analysis suggested a nonlinear distribution of the bond stress along the embedded portion of the bar. The proposed bond strength prediction equation, which considered the influence of bar diameter and embedment length, displayed good agreement with the experimental data.
| Type: | Thesis (Doctoral) |
|---|---|
| Qualification: | Ph.D |
| Title: | Bond of Basalt Fibre Reinforced Polymer Bars to Geopolymer Concrete |
| Open access status: | An open access version is available from UCL Discovery |
| Language: | English |
| Additional information: | Copyright © The Author 2022. Original content in this thesis is licensed under the terms of the Creative Commons Attribution-NonCommercial 4.0 International (CC BY-NC 4.0) Licence (https://creativecommons.org/licenses/by-nc/4.0/). Any third-party copyright material present remains the property of its respective owner(s) and is licensed under its existing terms. Access may initially be restricted at the author’s request. |
| UCL classification: | UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Engineering Science UCL > Provost and Vice Provost Offices > UCL BEAMS > Faculty of Engineering Science > Dept of Civil, Environ and Geomatic Eng UCL > Provost and Vice Provost Offices > UCL BEAMS UCL |
| URI: | https://discovery.ucl.ac.uk/id/eprint/10143392 |
Loading...
Loading...Loading...Loading...Archive Staff Only
 |
View Item |
