F. Caputo, G. Lamanna, A. Soprano¹

Structural Durability & Health Monitoring, Vol.7, No.4, pp. 283-296, 2011, DOI:10.3970/sdhm.2011.007.283

Abstract The present paper deals with a numerical investigation on hybrid bolted joints between unidirectional, quasi isotropic Carbon Fiber Reinforced Polymer (CFRP) composite and aluminium alloy plates, subjected to traction loads. CFRP composite materials are widely used in aerospace applications, where requirements of weight reduction and structural high performances are very compelling. Composite materials generally present high resistance to fatigue and corrosion but the presence of joints in the structure can cause structural problems and then decrease the structural reliability of jointed component.
A hybrid bolted joint constituted of a metal plate, made of aluminium alloy, and… More >

Saptarshi Sasmal¹, K. Ramanjaneyulu²

Structural Durability & Health Monitoring, Vol.7, No.4, pp. 253-282, 2011, DOI:10.3970/sdhm.2011.007.253

Abstract This paper proposes a methodology for damage detection in beam like structures using vibration characteristics obtained from transfer matrix technique. At first, vibration characteristics of beam-like structure have been determined with the help of a computer program developed based on the formulations presented in this paper. Then, a detailed study has been carried out to categorise the influence of damage on frequency and mode shape (both displacement and rotational) information. For a structure with known magnitude and location of damage(s), frequencies and mode shape information are obtained and the same has been used in determining… More >

Sangoju Bhaskar¹, Ravindra Gettu², B.H. Bharatkumar¹, M. Neelamegam¹

Structural Durability & Health Monitoring, Vol.7, No.4, pp. 231-252, 2011, DOI:10.3970/sdhm.2011.007.231

Abstract The durability of reinforced concrete (RC) exposed to severe environments depends largely on its ability to resist the penetration of aggressive compounds. This paper deals with the corrosion of reinforcement bars (rebars) in cracked concrete exposed to chlorides. A simple U-shaped specimen was used in the study, with a high yield strength deformed bar of 12 mm diameter placed at with 20 mm clear cover. Concrete specimens with three water to cement ratios (w/c) and pre-cracks exposed to chlorides were studied for quality assessment and quantifying the corrosion damage in terms of gravimetric weight loss. More >

A. Lanciotti, L. Lazzeri¹, C. Polese², C. Rodopoulos³, P. Moreira^4,5, A. Brot⁶, G. Wang⁷, L. Velterop⁸, G. Biallas⁹, J. Klement

Structural Durability & Health Monitoring, Vol.7, No.3, pp. 211-230, 2011, DOI:10.3970/sdhm.2011.007.211

Abstract An experimental activity was performed to collect test data on the fatigue crack propagation in various types of specimens, within the DaToN research project, partly funded by the EU in the FP6 programme. Only one general configuration was used, i.e. flat panels with two blade stringers, with different options for the manufacturing processes, that could be integral or welded. The purpose of this test activity was to obtain useful results for the validation and calibration of prediction methodologies, also developed in the same DaToN research project. A wide experimental programme was defined and performed by More >

S.M.O. Tavares¹, S.M. Häusler², P.M. Baiz³, P.M.S.T. de Castro¹, P. Horst² , M.H. Aliabadi³

Structural Durability & Health Monitoring, Vol.7, No.3, pp. 191-210, 2011, DOI:10.3970/sdhm.2011.007.191

Abstract This article is the second part of a two parts paper which presents, compares and discusses the different crack growth simulation models which were introduced for fatigue crack growth assessment during the DaToN project. In the first part, different simulation approaches were applied to determine a calibration of the stress intensity factors as a function of the crack length for a two stiffeners panel with a central crack. Due to the residual stress field promoted by the different manufacturing processes, its influence was included in the numerical models to determine the stress intensity factors. In… More >

S.M. Häusler¹, P.M. Baiz², S.M.O. Tavares³, A. Brot⁴, P. Horst¹, M.H. Aliabadi², P.M.S.T. de Castro³, Y. Peleg-Wolfin⁴

Structural Durability & Health Monitoring, Vol.7, No.3, pp. 163-190, 2011, DOI:10.3970/sdhm.2011.007.163

Abstract This article represents the first part of a two-part article which presents, compares and discusses the different crack growth simulation models which were introduced for fatigue crack growth assessment during the DaToN project. The project was funded by the EC within the 6th framework program and was specifically devoted to investigate innovative manufacturing techniques for metallic structures with special focus on the effects of residual stresses on the fatigue crack growth and residual strength behaviour. Within this first part the different simulation approaches, including the residual stress modelling approaches will be introduced and stress intensity… More >

A. Brot¹, I. Kressel¹

Structural Durability & Health Monitoring, Vol.7, No.3, pp. 153-162, 2011, DOI:10.3970/sdhm.2011.007.153

Abstract Analysis and testing of integrally stiffened aluminum panels, reinforced by carbon-epoxy or boron-epoxy bonded strips, is described. Fatigue testing was performed at room-temperature and at -50°C. The test results show a very significant increase in the crack growth life of these panels after the reinforcement. The analytical results, based on finite-element models, correlated very well with the test results. More >

A.V. Ekhlakov², O.M. Khay², Ch. Zhang², J. Sladek³, V. Sladek³

Structural Durability & Health Monitoring, Vol.6, No.3&4, pp. 329-350, 2010, DOI:10.3970/sdhm.2010.006.329

Abstract In this paper, transient crack analysis in two-dimensional, isotropic, continuously non-homo -ge -neous and linear elastic functionally graded materials is presented. A boundary-domain element method based on boundary-domain integral representations is developed. The Laplace-transform technique is utilized to eliminate the dependence on time. Laplace-transformed fundamental solutions of linear coupled thermoelasticity for isotropic, homogeneous and linear elastic solids are applied to derive boundary-domain integral equations. The numerical implementation is performed by using a collocation method for the spatial discretization. The time-dependent numerical solutions are obtained by the Stehfest's inversion algorithm. For an edge crack in a More >

G. Dhondt¹, D. Bremberg²

Structural Durability & Health Monitoring, Vol.6, No.3&4, pp. 305-328, 2010, DOI:10.3970/sdhm.2010.006.305

Abstract In a previous article the K-distritubion along the crack front of several mixed-mode specimens was investigated [Dhondt, Chergui, and Buchholz (2001)]. Both the modified virtual crack closure integral method and the quarter point element stress field method yielded results close to the available reference solutions in the literature [Murakami (1987)]. The present paper extends these results in two aspects. First, the meshing procedure used to obtain a focused mesh at the crack front is modified in order to deal with highly curved cracks. Secondly, the K-distribution along the initial crack is used to perform a More >

Masanori Kikuchi¹, Kazuhiro Suga¹

Structural Durability & Health Monitoring, Vol.6, No.3&4, pp. 289-304, 2010, DOI:10.3970/sdhm.2010.006.289

Abstract Crack closure effect on interaction of two surface crack growth processes by fatigue is studied. At first, change of C value in Paris' law along crack front of single surface crack is measured experimentally. It is shown that C value decreases near specimen surface. Crack closure effect is studied numerically for a surface crack by elastic-plastic cyclic analyses. It is found that closure effect appears more strongly near specimen surface than the maximum-depth point. By determining effective stress intensity factor including closure effect, it is shown that change of C value is equal to the More >