The performance of concrete cover as a thermal insulation for BFRP bars in tension at early stage of fire

• Autorzy: Wydra Małgorzata , Sadowski Grzegorz , Dolny Piotr , Turkowski Piotr , Fangrat Jadwiga

Identyfikatory

DOI

10.15199/33.2025.05.02

Warianty tytułu

PL

Zastosowanie otuliny betonowej jako izolacji termicznej prętów BFRP podczas rozciągania we wczesnej fazie pożaru

• Języki publikacji: EN PL

Abstrakty

EN

Despite multiple beneficial mechanical properties and low ecological impact, limited recognition of the properties of relatively new Basalt Fibre Reinforced Polymer (BFRP) reinforcement bars, especially at elevated and high temperature range, still limits the area of their potential applications in building structures. In this study the performance of such bars in tension during heating up to 200°C in steady state regime, and the performance of concrete cover were investigated. Due to limited data available in terms of elasticity modulus values changes for FRP at elevated temperatures, the Digital Image Correlation (DIC) was used for strain analysis in this study. There was no clearly positive influence of concrete cover on the maximum value of observed stresses. This may be attributed to the loss of bond between concrete and BFRP bars, as well as negligible values of registered strains at the concrete surface were registered.

PL

Pomimo wielu korzystnych właściwości mechanicznych i niewielkiego wpływu na środowisko, niedostateczne rozpoznanie właściwości stosunkowo nowych prętów zbrojeniowych z polimeru wzmocnionego włóknem bazaltowym (ang. Basalt Fibre Reinforced Polymer – BFRP), szczególnie w podwyższonej i wysokiej temperaturze, nadal ogranicza obszar ich potencjalnego zastosowania w konstrukcjach budowlanych. W pracy prezentowanej w artykule zbadano charakterystykę takich prętów przy rozciąganiu podczas nagrzewania do 200°C w stanie ustalonym oraz skuteczność ich otuliny betonowej. Ze względu na ograniczoną liczbę dostępnych danych dotyczących zmian wartości modułu sprężystości BFRP w podwyższonej temperaturze, do analizy odkształceń w tym badaniu wykorzystano cyfrową korelację obrazu (ang. Digital Image Correlation – DIC). Nie zaobserwowano pozytywnego wpływu otuliny na maksymalną wartość naprężeń, co można przypisać utracie wiązania między otuliną a prętami BFRP. Ponadto zarejestrowano znikome wartości odkształceń na powierzchni betonu.

Słowa kluczowe

EN

basalt fiber reinforced polymer; BFRP bar; reinforcing bar; elevated temperature; high temperature; tension; concrete cover; thermal insulation; fire

PL

polimer wzmocniony włóknami bazaltowymi; pręt BFRP; pręt zbrojeniowy; temperatura podwyższona; temperatura wysoka; rozciąganie; otulina betonowa; izolacja cieplna; pożar

• Wydawca: Wydawnictwo SIGMA-NOT
• Czasopismo: Materiały Budowlane
• Rocznik: 2025
• Tom: nr 5
• Strony: 10--15
• Opis fizyczny: Bibliogr. 24 poz., il., tab.

Twórcy

autor

Wydra Małgorzata

• University of Michigan, Ann Arbor, United States of America

• https://orcid.org/0000-0002-4629-9656

autor

Sadowski Grzegorz

• Warsaw University of Technology, Faculty of Civil Engineering, Mechanics and Petrochemistry

• https://orcid.org/0000-0001-6441-0875

autor

Dolny Piotr

• Warsaw University of Technology, Faculty of Civil Engineering, Mechanics and Petrochemistry

• https://orcid.org/0000-0002-5384-9257

autor

Turkowski Piotr

• Building Research Institute

• https://orcid.org/0000-0002-0020-0091

autor

Fangrat Jadwiga

• Building Research Institute

• https://orcid.org/0000-0002-7871-0032

Bibliografia

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