Gouravaraju Saipraneeth¹, Ranjan Ganguli²

Structural Durability & Health Monitoring, Vol.7, No.1&2, pp. 23-64, 2011, DOI:10.3970/sdhm.2011.007.023

Abstract In this paper, the effect of damage on mode shape related parameters of a beam is investigated. The damage is represented by a localized reduction in beam stiffness. The damage location and amount is varied using a finite element model of the beam to obtain the mode shapes. A beam which is simply supported at both ends is used for the numerical results. The periodic nature of the beam is exploited to obtain spatial Fourier coefficients of the mode shapes. As the damage location and size are varied, it is found that the Fourier coefficients More >

Dennis Bäcker¹, Andreas Ricoeur², Meinhard Kuna¹

Structural Durability & Health Monitoring, Vol.7, No.1&2, pp. 1-22, 2011, DOI:10.3970/sdhm.2011.007.001

Abstract A new sensor concept for monitoring fatigue crack growth in technical structures is presented. It allows the in-situ determination of the position of the crack tip as well as the fracture mechanical quantities. The required data are obtained from a piezoelectric polymer film, which is attached to the surface of the monitored structure. The stress intensity factors and the crack tip position are calculated from electrical potentials obtained from a sensor array by solving the non-linear inverse problem. More >

K.N. Song¹

Structural Durability & Health Monitoring, Vol.7, No.4, pp. 297-306, 2011, DOI:10.3970/sdhm.2011.007.297

Abstract The IHX (Intermediate Heat Exchanger) of a VHTR (Very High Temperature Reactor) transfers 950° heat generated from the VHTR to a hydrogen production plant. The Korea Atomic Energy Research Institute (KAERI) has manufactured a small-scale prototype of a PCHE (Printed Circuit Heat Exchanger) under consideration as a candidate of the IHX. In this study, as a part of high-temperature structural integrity evaluation of the small-scale PCHE prototype, we carried out a macroscopic structural behavior analysis including structural analysis modeling and thermal/elastic structural analysis under small-scale gas loop test conditions as a precedent study to a More >

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 >