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M. Ševčík et al, Frattura ed Integrità Strutturale, 34 (2015) 216-225; DOI: 10.3221/IGF-ESIS.34.23 224 comparison of the experimental data points and predicted fracture response for the crack propagating exclusively in Path II using mixed-mode fracture criterion is shown in Fig. 12. Figure 11 : Experimentally obtained fracture criterion based on the mixed-mode delamination tests [14]. Figure 12 : Comparison of experimental data points of MMB-01 to MMB-05 from [14] with predicted behavior using mixed- mode fracture criterion ( c = 227 mm, c g = 54 mm). The predicted load vs. crack length diagram using mixed-mode fracture criterion is in both qualitative and quantitative agreement with experimentally obtained data. The scatter in experimental results is far greater than difference between polynomial fit of the experimental data and predicted behavior. Utilizing the proposed analytical model of asymmetrical mixed-mode bending test together with the mixed-mode fracture criterion opens possibility for optimization of the laminate lay-up, reduction of the specimen size as well as for the design of adhesively bonded joints of more than two laminates. The only requirement is that the stacking sequence of the laminate remains the same in the vicinity of the crack propagation path otherwise new mixed-mode fracture criterion has to be experimentally obtained. C ONCLUSIONS his paper is focused on the problematic of the mixed-mode bending test of adhesively bonded fiber reinforced polymer composites with special emphasize on the mixed-mode bending test. A new analytical model for the calculation of the total strain energy release rate is derived and compared with well established relation of Reeder and Crews. On the practical example it is shown that for symmetrical MMB specimens the proposed relation gives equivalent values and it is therefore more generalized and possibly applicable for asymmetric specimens. In the second part of the paper the proposed analytical model is used for the prediction of the load vs. crack length diagram of the MMB test of the real specimens. It is shown that the proposed model can predict the fracture behavior in various layers and therefore to describe the fracture behavior in more details. The methodology and results presented in this paper could be utilized for the design of both joint geometry and lay-up of the laminates constituting the joint or for the prediction of the fracture behavior of such structures. A CKNOWLEDGEMENTS his work was supported through the grant 15-09347S of the Czech Science Foundation and by the Ministry of Education, Youth and Sports of the Czech Republic throughout the Project No. CZ.1.07/2.3.00/30.0063 “Talented postdocs for scientific excellence in physics of materials”. R EFERENCES [1] Gowayed, Y., Types of fiber and fiber arrangement in fiber-reinforced polymer (FRP) composites. In: Uddin N, editor. Developments in Fiber-Reinforced Polymer (FRP) Composites for Civil Engineering, Woodhead Publishing, (2013) 3-17. T T