• Title/Summary/Keyword: Tresca criterion

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Reliability Estimation of Solder Joint by Using Failure Probability Model (파손확률 모델을 이용한 솔더 조인트의 건전성 평가)

  • Myoung, No-Hoon;Lee, Ouk-Sub;Kim, Dong-Hyeok
    • Proceedings of the KSME Conference
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    • 2004.04a
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    • pp.365-370
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    • 2004
  • Generally, component and FR-4 board are connected by solder joint. Because material properties of components and FR-4 board are different, component and FR-4 board show different coefficients of thermal expansion (CTE) and thus strains in component and board are different when they are heated. That is, the differences in CTE of component and FR-4 board cause the dissimilarity in shear strain and solder joint' failure. The first order Taylor series expansion of the limit state function incorporating with Tresca failure criterion is used in order to estimate the failure probability of solder joints under heated condition. Using shear stresses and shear strains appeared on the solder joint, we estimate the failure probability of solder joints with the Tresca failure criterion. The effects of random variables such as CTE, distance of the solder joint from the neutral point(DNP), temperature variation and height of solder on the failure probability of the solder joint are systematically studied by using the failure probability model with first order reliability method(FORM).

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Undrained solution for cavity expansion in strength degradation and tresca soils

  • Li, Chao;Zou, Jin-feng;Sheng, Yu-ming
    • Geomechanics and Engineering
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    • v.21 no.6
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    • pp.527-536
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    • 2020
  • An elastic-plastic solution for cavity expansion problem considering strength degradation, undrained condition and initial anisotropic in-situ stress is established based on the Tresca yield criterion and cavity expansion theory. Assumptions of large-strain for plastic region and small-strain for elastic region are adopted, respectively. The initial in-situ stress state of natural soil mass may be anisotropic caused by consolidation history, and the strength degradation of soil mass is caused by structural damage of soil mass in the process of loading analysis (cavity expansion process). Finally, the published solutions are conducted to verify the suitability of this elastic-plastic solution, and the parametric studies are investigated in order to the significance of this study for in-situ soil test.

Plastic limit analysis of a clamped circular plate with unified yield criterion

  • Ma, Guowei;Hao, Hong;Iwasaki, Shoji
    • Structural Engineering and Mechanics
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    • v.7 no.5
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    • pp.513-525
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    • 1999
  • This paper presents exact close form solutions of plastic limit loads of a clamped circular plate under uniformly distributed load with different loading radii. A unified yield criterion, which includes a family of piecewise linear yield criteria and the commonly adopted yield criteria such as the Tresca criterion and the maximum principal deviatoric stress criterion or the twin shear stress criterion that are its special cases, and the Mises criterion can be approximated by it, is employed in the analysis. The plastic limit loads, moment fields and velocity fields of the clamped circular plate are calculated based on the unified yield criterion. The influences of the yield criteria, the edge effects and the loading radius on the plastic limits of the clamped circular plate are investigated. Analytical results are calculated and compared. The exact close form solutions presented in this paper provide efficient approaches for obtaining plastic limit loads and the corresponding moments and velocities of the clamped circular plates. The previously derived solutions based on the Tresca and the Mises criteria are its special cases.

A Estimation Method of Settlement for Granular Compaction Pile (조립토 다짐말뚝의 침하량 산정기법)

  • Kim, Hong-Taek;Hwang, Jung-Soon;Park, Jun-Yong;Yoon, Chang-Jin
    • Proceedings of the Korean Geotechical Society Conference
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    • 2005.03a
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    • pp.286-293
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    • 2005
  • In soft ground the settlement criterion usually governs. Therefore, it is very important not only reasonable assessment of the allowable bearing capacity of the soil but also reasonable assessment of settlement. In the previous studies by many other researchers, load concentration ratio and settlement reduction factor are usually proposed for estimating the settlement of granular compaction piles. In the previous studies, the reinforced ground with granular compaction piles is simplified as composite ground and the analysis is performed with in the basis of this assumption. However, the lateral deformation of granular compaction pile could not be considered and only the relative vertical strength between pile and soils could be considered in the analysis. In this study, a method adapting the Tresca failure criterion is proposed for calculating settlement of granular compaction pile. Proposed method can be considered the strength of pile material, pile diameter, installing distance of pile and the deformation behavior of vertical and horizontal directions of pile. In the presented study, large-scale field load test is performed and the results are described. Also, predictions of settlements from the proposed method are compared with the results of the load test. In addition, a series of parametric study is performed and the design parameters are analyzed.

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Kinematics of the Nonsteady Axi-symmetric Ideal Plastic Flow Process

  • Alexandrov, S.;Lee, W.;Chung, K.
    • Fibers and Polymers
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    • v.5 no.3
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    • pp.209-212
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    • 2004
  • A nonsteady axi-symmetric ideal flow solution is obtained here. It is based on the rigid perfect-plastic constitutive law with the Tresca yield condition and its associated flow rule. The process is to deform a circular solid disk into a spherical shell of prescribed geometry. It is assumed that there are no rigid zones and friction stresses. The solution obtained provides the distribution of kinematic variables and involves one undetermined function of the time. This function can be in general found by superimposing an optimality criterion.

Influence of the Intermediate Principal Stress on Behavior of Overconsolidated Clay (중간주응력(中間主應力)이 과압밀점토(過壓密粘土)의 거동(擧動)에 미치는 영향(影響))

  • Hong, Won Pyo
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.8 no.2
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    • pp.99-107
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    • 1988
  • A limited number of cubical triaxial tests with independent control of the three principal stresses were performed on an overconsolidated clay. The cubical undisturbed specimens with overconsolidation ratio of 5 were prepared in triaxial chamber after sampling in field. It was found that the intermediate principal stress influences on the stress-strain, undrained strength effective strength, effective friction angle and pore pressure of the overconsolidated clay. When the magnitude of the intermediate principal stress is not same as the minimum principal stress, the failure strength of the overconsolidated clay is underestimated by use of Mohr-Coulomb failure criterion while it can be estimated quite well by use of Lade failure criterion. And the undrained strength of the overconsolidated clay does not coincide with that obtained by Tresca failure criterion.

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Three Dimensional Strength Characterisics of Compressible Sand (압축성 모래의 3차원 전단강도 특성)

  • Park, Byeong-Gi;Jeong, Jin-Seop;Im, Seong-Cheol
    • Geotechnical Engineering
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    • v.6 no.3
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    • pp.65-76
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    • 1990
  • A series of consolidated drained and untrained cubical triaxial tests were performed to investigate three dimensional strength characteristics of compressible sand. All specimens, which are formed by deposisting a fine sand loosely, were used. Failure strength in terms of effective stress analysis was greatly influenced by the variation of intermediate principal stress and so was failure criterion The adjusted effective frictional angles obtained by the stress state projected on the same octahedral plane showed almost same value, while the measured effective frictional angles showed considerable difference depending on the drainage conditions. Results of total stress analysis in undrained test turned out to fit Tresca's failure criterion well, but results of effective stress analysis turned out to fit Lade's failure criterion well.

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Flare Test and Stress Analysis of Alloy 600/690 Tubes

  • Kim, W. G.;J. Jang;I. H. Kuk
    • Nuclear Engineering and Technology
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    • v.29 no.2
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    • pp.138-147
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    • 1997
  • Korean-made alloys 600 and 690 tubes were evaluated by flare tests according to ASTM standards, and acting stresses during the test ore analyzed. All the tubes, including alloys 600 and 690 tubes with various heat treatment conditions, satisfied the requirement with 30 or 35750.D expansion. Axial stresses in alloy 690 tubes were higher than those in alloy 600 ones and the gap increased gradually with flaring percentage(F.P, %). Assuming the tubes as the rigid-perfectly plastic body, a stress equation was obtained using modified Tresca's yield criterion. Also microstructural change of the flared tubes was discussed with the acting stresses.

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Thermoelastoplastic response of FGM linearly hardening rotating thick cylindrical pressure vessels

  • Ebrahimi, Tayebeh;Nejad, Mohammad Zamani;Jahankohan, Hamid;Hadi, Amin
    • Steel and Composite Structures
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    • v.38 no.2
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    • pp.189-211
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    • 2021
  • An analytical solution is presented to analyze the thermoelastoplastic response of a rotating thick-walled cylindrical pressure vessel made of functionally graded material (FGM). The analysis is based on Tresca's yield condition, its associated flow rule and linear strain hardening material behaviour. The uncoupled theory of thermoelasticity is used, and the plane strain condition is assumed. The material properties except for Poisson's ratio, are assumed to vary nonlinearly in the radial direction. Elastic, partially plastic, fully plastic, and residual stress states are investigated. The heat conduction equation for the one-dimensional problem in cylindrical coordinates is used to obtain temperature distribution in the vessel. It is assumed that the inner surface is exposed to an airstream and that the outer surface is exposed to a uniform heat flux. Tresca's yield criterion and its associated flow rule are used to formulate six different plastic regions for a linearly hardening condition. All these stages are studied in detail. It is shown that the thermoelastoplastic stress response of a rotating FGM pressure vessel is affected significantly by the nonhomogeneity of the material and temperature gradient. The results are validated with those of other researchers for appropriate values of the system parameters and excellent agreement is observed.

An Analysis on Surface Cracking Due to Thermomechanical Loading

  • Kim, S.S.;Lee, K.H.;Lee, S.M.
    • Tribology and Lubricants
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    • v.11 no.5
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    • pp.172-176
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    • 1995
  • This study deals with thermomechanical cracking between the friction surface and the interior of the brake disc. Analytical model considered in this study was a semi-infinite solid subjected to the thermal loading of an asperity moving with a high speed. The temperature field and the thermal stress state were obtained and discussed on the basis of Von Mises and Tresca Yielding Criterion. Analytical results showed that the dominant stress in cracking of friction brake is thermal stress and cracking location is dependent on the friction coefficient of contact and Peclet number. On the basis of analytical results thermomechanical cracking model is proposed.