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Combined experimental–numerical mode I fracture characterization of the pultruded composite bars

Smolnicki Michał, Duda Szymon, Zielonka Paweł, Stabla Paweł, Lesiuk Grzegorz, Lopes Cristiane Caroline Campos

Archives of Civil and Mechanical Engineering

2023

Vol. 23, no. 3

art. no. e146, 2023

In this paper, pultruded GFRP bars are investigated to determine their fracture properties. The double cantilever beam test (DCB) is used to assess fracture behavior under mode I loading conditions. However, due to the presence of the R-curve effect (variable fracture energy dependent on the length of the crack), it is necessary to introduce a nonstandard approach to determine fracture properties. The mixed experimental–numerical approach is proposed to deal with this issue. Numerical simulations were carried out in Simulia Abaqus, and with Python scripting it was possible to generate models and obtain R-curve for the material. The numerical model built based on the experimental results has very good agreement with it (force–displacement and delamination length–time characteristics) which allows the use of the mentioned model in the analysis of more complex structures. Acoustic emission analysis was introduced as an auxiliary technique. The delamination obtained from both the numerical model and the experiment complies with the registered acoustic emission events. The proposed method can be used in preparing a material model for other composite materials, which display the presence of the R-curve effect.

Projektowanie mostowych konstrukcji sprężonych - wybrane zagadnienia - cz. I

Oleszek R.

Mosty

2016

nr 2

68--70

W artykule poruszono kilka zagadnień związanych z założeniami projektowymi i klasyfikacją mostowych konstrukcji sprężonych z uwagi na charakter pracy przekrojów i stopień sprężenia. Omówiono ograniczenia naprężeń w betonie i stali sprężającej z nieaktualnej już normy PN-S-10042:1991 [11] i obowiązujących PN-EN 1992 [9, 10]. Przedstawiono i skomentowano wybrane aspekty obliczeniowe wynikające z dopuszczenia przez Eurokod 2 zarysowania w konstrukcjach sprężonych.

The classification of prestressed bridges in terms of beam cross-sections action mechanism and the degree of compression is presented. The selected aspects of post-tensioned concrete bridge structures design procedures are presented, based on the existing Polish Norms (PN) and current regulations according to Eurocodes. The procedures and design assumptions are compared to each other and their similarities and differences are discussed. The initial conditions for the design, associated with this issue, are discussed. Some aspects of the calculation, resulting from accepting cracking of prestressed bridge beams by Eurocode, are presented and commented. Finally, recommendations concerning the design procedures are formulated.