Mesomechanical analysis for the interface between FRP sheet & concrete Brief
introduction The damage between FRP sheet & concrete happens in very small scale, so mesomechanics are introduced to analyze the bonding behaviors. Paper download Meso-scale finite element model for FRP sheets/plates bonded to concrete. Engineering Structures. 2005. 27(4). 564- 575 ABSTRACT External bonding of fiber reinforced polymer (FRP) plates or sheets has recently emerged as a popular method for the strengthening of reinforced concrete (RC) structures. The behavior of such FRP-strengthened RC structures is often controlled by the behavior of the interface between FRP and concrete, and this interfacial behavior is commonly studied through a pull test in which an FRP sheet or plate is bonded to a concrete prism and is subject to tension. In this paper, a meso-scale finite element (FE) model implemented with the MSC.MARC program is presented for the simulation of interfacial debonding failures in a pull test. In this model, very small nearly square elements (0.25 mm to 0.5mm in size) are used with the fixed angle crack model (FACM) to capture the development and propagation of cracks in the concrete layer adjacent to the adhesive layer. The effect of element size is taken into account in modeling both the tensile and shear behavior of cracked concrete. Comparisons between the predictions of this model and test results are presented to demonstrate the capability and accuracy of this FE model. The debonding mechanism is also examined using results obtained with the FE model. Finally, a method for the determination of the local bond-slip curve of the FRP-to-concrete interface from the FE results is described. MESO-SCALE FINITE ELEMENT MODEL FOR FRP SHEETS/PLATES EXTERNALLY BONED TO CONCRETE Engineering Mechanics (Accepted) Abstract£ºExternal bonding of fiber reinforced polymer (FRP) plates or sheets has recently emerged as a popular method for the strengthening of reinforced concrete (RC) structures. The behavior of such FRP-strengthened RC structures is often controlled by the behavior of the interface between FRP and concrete. In this paper, a meso-scale finite element (FE) model is presented for the simulation of interfacial debonding failures in FRP-to-concrete bonded joints in pull test. In this model, very small elements (0.25 mm to 0.5mm in size) are used with crack band model to capture the development and propagation of cracks in the concrete layer adjacent to the adhesive layer. The effect of element size is taken into account in modeling both the tensile and shear behavior of cracked concrete. Comparisons between the predictions of this model and test results are presented to demonstrate the capability and accuracy of this FE model. The debonding mechanism is also examined using results obtained with the FE model. Key words£ºFRP, concrete, strengthen, bond, debonding, finite element analysis Bond-slip models for FRP sheet/plate-to-concrete interfaces, Abstract: A meso-scale finite element model is first presented for simulating the debonding behavior of FRP-to-concrete bonded joints in simple shear tests. In this model, both the FRP plate/sheet and the concrete are modeled using elements of mesoscopic sizes so that the shapes and paths of cracks during the entire debonding process can be appropriately captured. Results obtained from this model are next presented to provide insight into the debonding failure process. Finally, based on a finite element parametric study and existing test results, three bond-slip models of different levels of sophistication are presented. These proposed models are far more accurate than all existing bond-slip models.
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