C.M. Hefferan¹, S.F. Li¹, J. Lind¹, U. Lienert², A.D. Rollett³, P. Wynblatt³, R.M. Suter^1,3

CMC-Computers, Materials & Continua, Vol.14, No.3, pp. 209-220, 2009, DOI:10.3970/cmc.2009.014.209

Abstract We have measured and reconstructed via forward modeling a small volume of microstructure of high purity, well annealed nickel using high energy x-ray diffraction microscopy (HEDM). Statistical distributions characterizing grain orientations, intra-granular misorientations, and nearest neighbor grain misorientations are extracted. Results are consistent with recent electron backscatter diffraction measurements. Peaks in the grain neighbor misorientation angle distribution at 60 degrees (∑3) and 39 degrees (∑9) have resolution limited widths of ≈ 0.14 degree FWHM. The analysis demonstrates that HEDM can recover grain and grain boundary statistics comparable to OIM volume measurements; more extensive data sets More >

A.Iwasaki¹, K.Yuguchi², A.Todoroki³, Y.Shimamura⁴

The International Conference on Computational & Experimental Engineering and Sciences, Vol.6, No.3, pp. 183-188, 2008, DOI:10.3970/icces.2008.006.183

Abstract The present study is about study on the diagnostic accuracy of the unsupervised damage diagnosis method named SI-F method. For the health monitoring of existing structures, modeling of entire structure or obtaining data sets after creating damage for training is almost impossible. This raises significant demand for development of a low-cost diagnostic method that does not require modeling of entire structure or data on damaged structure. Therefore, the present study proposes a low-cost unsupervised statistical diagnostic method for structural damage detection. The proposed method statistically diagnoses structural condition by means of investigating the change of… More >

R. Issa¹, D. Violeau¹

CMC-Computers, Materials & Continua, Vol.8, No.3, pp. 151-164, 2008, DOI:10.3970/cmc.2008.008.151

Abstract Breaking waves can run up at the shoreline, inundating coastal regions and causing large property damage and loss of life. In order to proceed to the design of sea defence structures and estimate the possible damage resulting from sea submersion due to a tsunami for instance, it is thus crucial to understand these phenomena. However, due to the mathematical difficulties caused by the complexities of the fluid motion associated with breaking wave, a fully theoretical approach is not possible. Thus most of the investigations regarding breaking waves are experimental and numerical. Some methods were recently… More >

L.M. Xu¹, H. Fan^2,3, X M Xie³, C. Li³

CMC-Computers, Materials & Continua, Vol.7, No.3, pp. 119-128, 2008, DOI:10.3970/cmc.2008.007.119

Abstract In the present study we performed finite element simulation for bi-continuous heterogeneous solids via a random distribution of materials to predict effective elastic properties. With a random distributing scheme, a statistical analysis via finite element becomes feasible for the multi-phase heterogeneous solids. Using a two-phase bi-continuous material as example, the numerical prediction of the effective properties is obtained in terms of a mean value and standard deviation with a sample size of 30 for each of given volume fraction. The finite element simulation results fall within the analytical bounds proposed by Hashin and Shtrikman (1963) More >

A.H.W. Ngan¹

The International Conference on Computational & Experimental Engineering and Sciences, Vol.4, No.3, pp. 137-144, 2007, DOI:10.3970/icces.2007.004.137

Abstract When a random structure is loaded by far-field stresses, the elements inside will not be subject to the same forces because of structural inhomogeneities. Such a system represents an interesting analog to a thermal system at equilibrium -- the structural irregularities qualify for a description by a Shannon-like entropy, and there is also the usual (e.g. elastic) strain energy. When an entropy is related to energy, one immediately steps into the familiar field of statistical mechanics, but for a strained random structure, the real (Kelvin) temperature plays no role. Instead, an effective temperature exists but More >

Jae Bong Lee¹, Jai Hak Park¹, Sung Ho Lee², Hong-Deok Kim², Han-Sub Chung²

CMES-Computer Modeling in Engineering & Sciences, Vol.11, No.1, pp. 9-16, 2006, DOI:10.3970/cmes.2006.011.009

Abstract The growth of stress corrosion cracks in steam generator tubes is predicted using the Monte Carlo simulation and statistical approaches. The statistical parameters that represent the characteristics of crack growth and crack initiation are derived from in-service inspection (ISI) non-destructive evaluation (NDE) data. Based on the statistical approaches, crack growth models are proposed and applied to predict crack distribution at the end of cycle (EOC). Because in-service inspection (ISI) crack data is different from physical crack data, a simple method for predicting the physical number of cracks from periodic in-service inspection data is proposed in More >

Dongsheng Li^1,2, Ghazal Saheli¹, Moe Khaleel², Hamid Garmestani¹

CMC-Computers, Materials & Continua, Vol.4, No.1, pp. 31-42, 2006, DOI:10.3970/cmc.2006.004.031

Abstract A multiscale model based on statistical continuum mechanics is proposed to predict the mechanical and electrical properties of heterogeneous porous media. This model is applied within the framework of microstructure sensitive design (MSD) to guide the design of the microstructure in porous lanthanum strontium manganite (LSM) fuel cell electrode. To satisfy the property requirement and compatibility, porosity and its distribution can be adjusted under the guidance of MSD to achieve optimized microstructure. More >

G. Bertrand¹

Structural Durability & Health Monitoring, Vol.1, No.3, pp. 185-192, 2005, DOI:10.3970/sdhm.2005.001.185

Abstract Each maintenance strategy demands for the definition of an inspection threshold and further inspection intervals. A general criterion for the calculation of the time to first inspection is high probability of detection of a certain crack size and low failure probability in case a predicted crack size was not detected. The proposed method demonstrates that a top down analysis of crack development from critical sizes to detectable sizes reveals an economic benefit with respect to the frequency of inspections. The dispersion of fatigue stress cycles at rupture obtained from component tests at riveted lap joints More >