The Experts below are selected from a list of 13002 Experts worldwide ranked by ideXlab platform
Sankaran Mahadevan - One of the best experts on this subject based on the ideXlab platform.
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Probabilistic Fatigue Life Prediction of composite materials
Fatigue Life Prediction of Composites and Composite Structures, 2010Co-Authors: Y. Liu, Sankaran MahadevanAbstract:Abstract This chapter discusses the use of probabilistic models to describe the Fatigue behavior of composite materials and to quantify the uncertainties in Fatigue Life Prediction. The chapter first reviews existing methods for probabilistic Fatigue Life Prediction and then discusses how to quantify the uncertainties in applied loading and material properties. Following this, a random process approach using the Karhunen-Loeve expansion technique is discussed to quantify the input uncertainties as well as their correlations. Probabilistic methods are presented to solve the time-dependent reliability problem. The probabilistic Life Prediction method is demonstrated under variable amplitude loading for several example problems.
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Probabilistic Fatigue Life Prediction of multidirectional composite laminates
Composite Structures, 2005Co-Authors: Y. Liu, Sankaran MahadevanAbstract:A new damage accumulation model for Fatigue Life Prediction of composite laminates is proposed in this study. The model is constructed on the ply level and uses a new multiaxial damage index to consider the damage caused by different stress components. The Fatigue Life is predicted based on the proposed model and experimental results of the unidirectional laminates. The numerical results are compared with the experimental data for balanced laminates. The predicted Fatigue lives agree with the experimental observations very well. The methodology for probabilistic Fatigue Life Prediction and reliability calculation is also presented.
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Strain-based probabilistic Fatigue Life Prediction of spot-welded joints
International Journal of Fatigue, 2004Co-Authors: Sankaran MahadevanAbstract:Abstract This paper develops a strain-based probabilistic Fatigue Life Prediction methodology for spot-welded joints under variable amplitude loading history. The loading history is multi-axial and is obtained from transient response analysis of a vehicle model. A 3D FE model of a simplified joint with four spot welds is developed and a static stress–strain analysis is performed first. Then a probabilistic Miner’s rule is combined with randomized strain–Life curve family and the stress–strain analysis result to develop a strain-based probabilistic Fatigue Life Prediction methodology for the spot weld. This new method is implemented and combined with FEA software, and is useful for reliability assessment of spot-welded joints against Fatigue.
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Probabilistic Fatigue Life Prediction of spot-welded joints
International Journal of Materials & Product Technology, 2003Co-Authors: Sankaran MahadevanAbstract:A probabilistic Fatigue Life Prediction methodology for spot-welded joints under variable amplitude loading history is presented. The loading history is multi-axial and is obtained from transient response analysis of a vehicle model. A 3-D finite element (FE) model of a simplified joint with four spot welds is developed first to perform static stress analysis. Then, the probabilistic Miner's rule is combined with this stress analysis result to develop a probabilistic Fatigue Life Prediction methodology for the spot weld. This new method is implemented with MSC/Fatigue and is useful for reliability assessment of spot-welded joints against Fatigue.
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damage tolerance approach for probabilistic pitting corrosion Fatigue Life Prediction
Engineering Fracture Mechanics, 2001Co-Authors: Pan Shi, Sankaran MahadevanAbstract:Abstract The Fatigue damage process induced by pitting corrosion is composed of seven stages: pitting nucleation, pit growth, transition from pit growth to short crack, short crack growth, transition from short crack to long crack, long crack growth, and fracture. A comprehensive mechanics-based probabilistic model for pitting corrosion Fatigue Life Prediction by including all the seven stages is presented in this paper. An analytical first-order reliability method (FORM) and Monte Carlo simulation are implemented with the proposed model. Probabilistic sensitivity analysis is performed using the analytical FORM approach as well as through parametric studies. A numerical example is implemented for the application of the proposed method for the corrosion Fatigue Life Prediction of aluminum alloys. The cumulative distribution function of the Fatigue Life is obtained and the effect of several important random variables and their scatter on the Fatigue Life estimation is investigated.
Y. Liu - One of the best experts on this subject based on the ideXlab platform.
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Probabilistic Fatigue Life Prediction for concrete bridges using Bayesian inference
Advances in Structural Engineering, 2018Co-Authors: Ming Yuan, Yun Liu, Donghuang Yan, Y. LiuAbstract:A probabilistic Fatigue Life Prediction framework for concrete bridges is proposed in this study that considers the stress history from the construction stage to the operation stage. The proposed f...
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Fatigue Life Prediction for aging RC beams considering corrosive environments
Engineering Structures, 2014Co-Authors: Yibing Xiang, Lei Wang, Jianren Zhang, Y. LiuAbstract:A new crack growth-based corrosion Fatigue Life Prediction method for aging reinforced concrete beam is proposed in this paper. The proposed method couples the corrosion growth kinetics and Fatigue crack growth kinetics together. The relationship between corrosion damage morphology and corrosion loss is investigated by the experimental results. A phenomenological model is proposed to obtain the stress concentration factor model under different corrosion loss conditions. Following this, the developed model is integrated with an asymptotic method to calculate the stress intensity factor for the crack at corrosion pit roots. The Fatigue Life is predicted by the integration of the Fatigue crack growth rate curve from the equivalent initial flaw size to the critical length. Probabilistic analysis methodology is proposed to consider various sources of uncertainties for the Fatigue Life Prediction. Fatigue Life Prediction results are validated with experimental observations for various corroded steel bars and beams available in the literatures.
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Crack growth-based multiaxial Fatigue Life Prediction
2013Co-Authors: Y. LiuAbstract:A crack growth-based multiaxial Fatigue Life Prediction model is proposed in this paper, which uses a characteristic plane-based methodology for multiaxial Fatigue damage analysis and the Equivalent Initial Flaw Size (EIFS) concept for Life Prediction. The orientation of the characteristic plane is theoretically determined by minimizing the damage contribution of the hydrostatic stress amplitude and correlates with the material local failure modes. An equivalent stress intensity factor under the general multiaxial load is proposed. The Fatigue Life is predicted by integration from the EIFS to the critical crack length. The proposed model can be used for Fatigue Life Predictions of smooth specimens under both in-phase and out-of-phase loading conditions and can automatically adapt for different material failure mechanisms under various loading conditions. The Fatigue Life Prediction results are validated with experimental data for a wide range of metallic materials available in the literature. It is shown that model Predictions are in good agreement with experimental data under both proportional and nonproportional load.
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crack growth based Fatigue Life Prediction using an equivalent initial flaw model part i uniaxial loading
International Journal of Fatigue, 2010Co-Authors: Yibing Xiang, Y. LiuAbstract:A general methodology is proposed in this paper for Fatigue-Life Prediction using crack growth analysis. This is the part II of the paper and focuses on the Fatigue-Life Prediction under proportional and nonproportional multiaxial loading. The proposed multiaxial Fatigue-Life Prediction is based on a critical plane-based multiaxial Fatigue damage model and the Equivalent Initial Flaw Size (EIFS) concept. An equivalent stress intensity factor under general multiaxial proportional and nonproportional loading is defined. The Fatigue Life is predicted by integration of the crack growth rate curve from the EIFS to the critical crack length. The proposed model can automatically adapt for different materials experiencing different local failure modes. The numerical Fatigue-Life Prediction results calculated by the proposed approach are validated with experimental data for a wide range of metallic materials available in the literature. Reasonable agreements are observed between the model Predictions and the experimental observations under proportional and nonproportional loading.
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Probabilistic Fatigue Life Prediction of composite materials
Fatigue Life Prediction of Composites and Composite Structures, 2010Co-Authors: Y. Liu, Sankaran MahadevanAbstract:Abstract This chapter discusses the use of probabilistic models to describe the Fatigue behavior of composite materials and to quantify the uncertainties in Fatigue Life Prediction. The chapter first reviews existing methods for probabilistic Fatigue Life Prediction and then discusses how to quantify the uncertainties in applied loading and material properties. Following this, a random process approach using the Karhunen-Loeve expansion technique is discussed to quantify the input uncertainties as well as their correlations. Probabilistic methods are presented to solve the time-dependent reliability problem. The probabilistic Life Prediction method is demonstrated under variable amplitude loading for several example problems.
Sheri Sheppard - One of the best experts on this subject based on the ideXlab platform.
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Spot welds Fatigue Life Prediction with cyclic strain range
International Journal of Fatigue, 2002Co-Authors: Ning Pan, Sheri SheppardAbstract:Even though spot welds have been used widely in automotive manufacturing for years, Fatigue Life Prediction methods for estimating Life have been based on welds connecting sheets of the same thickness. A validated Fatigue Life Prediction method for spot welds connecting sheets of different thicknesses has yet to be published. In this study, the stresses and strains at the notch of a spot weld nugget were studied in detail. It was found that significant yielding occurs in spot welds even under relatively low loads. A Fatigue Life Prediction method based on strain is proposed. The work here shows that a strain-based approach does a very good job of describing the Fatigue Life of mixed-thickness spot welds.
Hong Tae Kang - One of the best experts on this subject based on the ideXlab platform.
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Fatigue Life Prediction of spot-welded joints with a notch stress approach
Theoretical and Applied Fracture Mechanics, 2020Co-Authors: Changjian Wei, Hong Tae KangAbstract:Abstract Spot-welded joints are widely used in the construction of vehicle structures and frequently become critical locations for Fatigue failure. Hence, it is essential to have reliable Fatigue Life Prediction method for the spot-welded joints during vehicle structure design. In this paper, a new notch stress approach is developed for Fatigue Life Prediction of the spot-welded joints. Currently, structural stress methods are widely used in automotive industry for Fatigue Life Prediction of spot-welded joints. However, these methods are not well considering local geometry information. This paper introduces a notch stress based method to overcome the limitation of the structural stress methods. In the notch stress method, stress concentration factors for spot-welded joints are calculated from stress intensity factor equations. Then, the notch stress method is validated with Fatigue test results of lap-shear and coach peel specimens.
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A notch stress method for Fatigue Life Prediction of spot-welded joints
MATEC Web of Conferences, 2019Co-Authors: Changjian Wei, Hong Tae KangAbstract:Spot-welded joints are widely used in the construction of vehicle structures and frequently become critical locations for Fatigue failure. Hence, it is essential to have reliable Fatigue Life Prediction method for the spot-welded joints during vehicle structure design. In this paper, a new notch stress approach is developed for Fatigue Life Prediction of the spot-welded joints. Currently, structural stress methods are widely used in automotive industry for Fatigue Life Prediction of spot-welded joints. However, these methods are not well considering local geometry information. This paper introduces a notch stress based method to overcome the limitation of the structural stress methods. In the notch stress method, stress concentration factors for spot-welded joints are calculated from stress intensity factor equations. Then, the notch stress method is validated with Fatigue test results of lap-shear and coach peel specimens.
Ning Pan - One of the best experts on this subject based on the ideXlab platform.
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Spot welds Fatigue Life Prediction with cyclic strain range
International Journal of Fatigue, 2002Co-Authors: Ning Pan, Sheri SheppardAbstract:Even though spot welds have been used widely in automotive manufacturing for years, Fatigue Life Prediction methods for estimating Life have been based on welds connecting sheets of the same thickness. A validated Fatigue Life Prediction method for spot welds connecting sheets of different thicknesses has yet to be published. In this study, the stresses and strains at the notch of a spot weld nugget were studied in detail. It was found that significant yielding occurs in spot welds even under relatively low loads. A Fatigue Life Prediction method based on strain is proposed. The work here shows that a strain-based approach does a very good job of describing the Fatigue Life of mixed-thickness spot welds.
