Experimental research on RC beams strengthened in shear with PBO-FRCM composites

21st International Scientific Conference on Advanced in Civil Engineering "Construction - The Formation of Living Environment"

土木建筑工程

Marcinczak, Dorota^1 ; Trapko, Tomasz^1

Wroclaw University of Science and Technology, Poland^1

关键词: Cementitious matrices;    Experimental research;    Failure mechanism;    High temperature;    Historical buildings;    Reinforced concrete beams;    Shear strengthening;    Strengthened beams;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/365/4/042035/pdf
DOI  :  10.1088/1757-899X/365/4/042035

学科分类：土木及结构工程学

来源: IOP

【 摘 要 】

The article presents an experimental research conducted on beams with PBO-FRCM shear strengthening with end-anchorage system. PBO-FRCM (Fibre Reinforced Cementitious Matrix) composites consist of mineral mortar and PBO (p-Phenylene Benzobis oxazol) composite fibres. Using of mineral mortar makes them as a good alternative to the commonly used FRP composites, especially in structures exposed to high temperatures and historical buildings. For FRCM composites most commonly failure mechanism is debonding of the fibers from mineral mortar with no rupture of fibres. To prevent premature debonding of the composite and increase the effectiveness of reinforcements FRCM suitable anchorage should be used. In this case, experimental research was conducted on 4 T-shaped reinforced concrete beams strengthened in a shear using PBO-FRCM with anchorage. One beam was a control beam without strengthening, and 3 beams had the same shear strengthening with PBO strip anchorage. All elements failed in a shear with formation of main diagonal crack. Despite the presence of anchorage, the failure mode of all strengthened beams was associated with debonding of PBO mesh accompanied by the development of diagonal crack. The PBO fibres were not ruptured in any of the beams. Despite the debonding, composite further transferred shear force. The failure mechanisms and strain in composites were analysed and described. The results confirmed that the PBO-FRCM system is an effective way of strengthening RC beams in a shear and that the effectiveness of this system is influenced by the presence of the anchorage.