Bending Behaviour of Prestressed T-Shaped Concrete Beams Reinforced with FRP—Experimental and Analytical Investigations

Abstract

Materials such as high performance (HPC) or ultra-high performance concrete (UHPC), and fibre-reinforced polymer (FRP) reinforcement can be used to improve the resource efficiency in concrete construction by, for example, enabling the production of thin-walled structures. When building filigree concrete beams two essential factors must be considered: the low stiffness of the structure and the bond between the materials. By prestressing the structural stiffness is improved while an adequate concrete cover ensures sufficient bond strength. Based on this the bending behaviour of prestressed T-shaped beams reinforced with FRP, focussing on determining the influence of four parameters on the bearing capacity, bond behaviour and failure mode, is investigated in this paper. Comprehensive experimental investigations prove the potential of the approach and show that a reduction of the web thickness down to 40 mm, a lower concrete quality, and the use of glass FRP instead of carbon FRP allow a more resource-efficient structure while the applied prestressing leads to a higher utilisation of the high performance materials.

A new concept of bio-based prestress technology with experimental Proof-of-Concept on Bamboo-Timber composite beams

“…Prestress technology has been widely used in reinforced concrete structures [1][2][3][4][5][6][7][8][9][10][11] to reduce deflection, increase structural stiffness, exploit the materials' mechanical strength, and ultimately, to create a lighter structural system to span longer distance. It is always the timber engineers' dream to develop an effective, practical, pure bio-based prestressed technology with in-situ flexibility that allows members to be cut and adjusted in-situ.…”

Experimental Investigations of the Bond Behavior between Carbon Rebars and Concrete in Germany

“…For example, they are utilized as reinforcement in concrete bridges to support high loads. While some publications have explored the tensile behavior of carbon rebars or components with mixed reinforcement of carbon rebars and grids in Germany and Austria [6][7][8][9][10], there is a lack of comprehensive information on the bond behavior between carbon rebars and concrete in Germany where only a few investigations had been conducted, e.g., [11][12][13]. Understanding the bond behavior is essential for safe and cost-effective design, calculation, and dimensioning of carbon-reinforced concrete structures.…”

Testing and Evaluation of Flexural Tensile Strength of Prestressed CFRP Cables

“…Carbon fiber-reinforced polymer (CFRP) is recognized in engineering as an ideal substitute for traditional steel tendons in harsh environments [ 1 , 2 , 3 , 4 , 5 ] due to its high strength, light weight, and high corrosion resistance, which can effectively reduce structural weight and improve structural durability [ 6 , 7 , 8 ]. In the 1980s, Japan, the United States, and other countries began to study its engineering applications [ 9 , 10 ] and the U.S. Specification ACI 440.4R-04 [ 11 ] recommends the use of CFRP cables as a prestressing material.…”