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Preparation of Aligned Steel Fiber Reinforced Cementitious Composite and Its Flexural Behavior
Published on: June 27, 2018
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Old Timber Reinforcement with FRPs
Janusz Brol1, Agnieszka Wdowiak-Postulak2
1Faculty of Civil Engineering, Silesian University of Technology, 44-100 Gliwice, Poland.
Materials (Basel, Switzerland)
|December 19, 2019
Summary
Carbon-fibre mats significantly enhanced the bending capacity of historic larch timber, while glass-fibre reinforced polymer (GFRP) showed minimal improvement. Repairs on aged pine beams using carbon-fibre reinforced polymer (CFRP) faced delamination challenges.
Area of Science:
- Structural Engineering
- Materials Science
- Timber Engineering
- Heritage Conservation
Background:
- Historic timber structures require effective strengthening methods to ensure longevity and safety.
- Assessing the performance of modern reinforcement materials on aged timber is crucial for conservation efforts.
- European larch (Larix decidua Mill.) and Scots pine (Pinus sylvestris L.) are common historic building materials.
Purpose of the Study:
- To evaluate the reinforcement effectiveness of various fiber-reinforced polymers (FRPs) on old larch and pine timber.
- To compare the flexural bending capacity enhancement provided by carbon-fibre, aramid-fibre, BFRPs, and GFRPs.
- To investigate the real-scale repair effectiveness and challenges, such as delamination, of aged timber beams using CFRP.
Main Methods:
- Flexural bending tests were conducted on old solid European larch timber samples reinforced with carbon-fibre and aramid-fibre mats and strips, BFRPs, and GFRPs.
- Real-size bending tests were performed on repaired 130-year-old pine beams using carbon-fibre reinforced polymer (CFRP) strips and mats.
- Analysis included quantifying the increase in flexural bending capacity and observing repair-related issues like delamination.
Main Results:
- Carbon-fibre mats yielded the highest increase in flexural bending capacity for larch timber (60.66%).
- Glass-fibre reinforced polymer (GFRP) reinforcement provided the lowest increase in flexural bending capacity (19.04%).
- Repairs on aged pine beams using CFRP strips encountered delamination issues due to uneven timber surfaces.
Conclusions:
- Carbon-fibre materials are highly effective for reinforcing old European larch timber, significantly improving its load-bearing capacity.
- GFRP reinforcement is less effective for enhancing the flexural performance of aged larch timber compared to carbon-fibre.
- Delamination presents a significant challenge for the long-term effectiveness of CFRP repairs on damaged, aged timber surfaces.
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