T. Nishioka¹, M.Kogame², T. Fujimoto¹, G. Okamoto¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.1, No.3, pp. 113-118, 2007, DOI:10.3970/icces.2007.001.113

Abstract In this study, we observed C.G.S. fringe pattern of dynamic fracture under impact load by an ultra high-speed CCD video camera, and stress intensity factors KI, KII are evaluated from the experimental measurements. From the evaluation of stress intensity factors, local mode I condition is observed during crack propagation. On the other hand, concentrated load is obtained by the experimental devices in this study. We suggest the least square method to estimate loading value based on the C.G.S. fringe pattern analyses. More >

T. Nishioka¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.1, No.3, pp. 105-112, 2007, DOI:10.3970/icces.2007.001.105

Abstract This paper summarizes recent discovery for the Governing Condition of Dynamic Crack Bifurcation Phenomena, which were found by the author's laboratory. More >

M. Kikuchi¹, S. Sannoumaru²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.1, No.3, pp. 99-104, 2007, DOI:10.3970/icces.2007.001.099

Abstract Thickness effect is studied experimentally. At free surface of the specimen, shear lip fracture pattern appears, though dimple fracture pattern is observed inside of the specimen. The area of shear-lip fracture changes due to the change of the specimen thickness. In this study, experimental study is conducted by changing specimen thicknesses. Fracture surfaces are precisely observed using SEM, and dimple patterns on them are observed. At the free surface, very narrow no-void area is observed. By using FRASTA technique, dimple fracture process is simulated. It is found that shear-lip fracture appears after dimple fracture process. FEM simulation is carried out… More >

G. Renaud¹, M. Liao¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.1, No.2, pp. 87-92, 2007, DOI:10.3970/icces.2007.001.087

Abstract This paper presents a probabilistic crack growth model developed for the Holistic Structural Integrity Process (HOLSIP) framework. Statistical data, obtained from testing and fractographic analyses of 2024-T3 test coupons, were used to derive the fatigue crack growth material variability. Results showed the relative impact of material variability in the short and long crack regimes. Monte Carlo simulations showed good agreement between analytical life distributions and test results. More >

P.D. Shah¹, C.L. Tan¹, X. Wang¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.1, No.2, pp. 75-80, 2007, DOI:10.3970/icces.2007.001.075

Abstract The path-independent mutual- or M-integral for the computation of the T-stress for interface cracks lying between dissimilar anisotropic, linear elastic solids is developed in this paper. For the numerical stress analysis, the Boundary Element Method (BEM) is employed and special crack-tip elements with the proper oscillatory traction singularity are used. The successful implementation of the scheme for evaluating the T-stress of an interface crack between anisotropic bi-materials with BEM is demonstrated by numerical examples. More >

Milazzo A.¹, aimo A.¹, Orl,o C.¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.1, No.2, pp. 69-74, 2007, DOI:10.3970/icces.2007.001.069

Abstract In this paper a Hierarchical approach for the analysis of advanced aerospace structures is presented. The proposed Global/Local model uses two kind of numerical methods for the different steps of analysis. In particular the first step of the Hierarchical procedure is performed by the Finite Element code Patran/NastranTM, while the local analysis is performed by using a Boundary Element code based on the multidomain anisotropic technique. The accuracy and the effectiveness of the model have been demonstrated analysing classical stress concentration problems. Then the procedure has been used to analyze more complex structure among which a riveted patch repair, applied… More >

K. Gordnian¹, H. Hadavinia¹, G. Simpson¹, A. Aboutorabi¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.1, No.2, pp. 61-68, 2007, DOI:10.3970/icces.2007.001.061

Abstract The compliance equation is used to calculate the energy release rate for angle ply laminated double cantilever composite beam specimen. Instead of the traditional approach of a beam on an elastic foundation, a second order shear thickness deformation beam theory (SSTDBT) has been considered. More >

B.K. Raghu Prasad¹, Renuka Devi M.V.²

The International Conference on Computational & Experimental Engineering and Sciences, Vol.1, No.2, pp. 55-60, 2007, DOI:10.3970/icces.2007.001.055

Abstract The concepts associated with concrete crack formation and propagation is discussed in the light of fractal and probability theories. These concepts are employed to model the tortuous crack path in a highly heterogeneous medium of concrete. Fictitious Crack Model (FCM)[1] is extended to analyze plain concrete beams with such tortuous cracks. The parametric study has been carried out in order to obtain the influence of various fracture parameters on the beam response. More >

C. Soutis¹, K. Diamanti¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.1, No.2, pp. 49-54, 2007, DOI:10.3970/icces.2007.001.049

Abstract A cost and time effective inspection strategy for in-service health monitoring of composites is demonstrated using the fundamental anti-symmetric A0 Lamb mode at frequencies of 15-20 kHz. In principle, this method involves analysis of the transmitted and/or reflected wave after interacting with the test-piece boundaries or discontinuities (defects). In the present work, the applicability of the technique to composite sandwich structures is explored. More >