• Title/Summary/Keyword: Ultimate

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Ultimate Uplift Capacity of Permanent Anchor Embedded in Weathered Rock (풍화암에 근입된 영구 앵커의 극한인발력)

  • Yoo, Nam-Jae;Park, Byung-Soo;Jeong, Gil-Soo;Kim, Jin-Hwang
    • Journal of Industrial Technology
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    • v.21 no.B
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    • pp.195-203
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    • 2001
  • The purpose of this study is to estimate ultimate uplift capacity of permanent anchor which was cast into weathered rock. The ultimate uplift capacity was estimated from the load-displacement curve of four different anchors which have different bond length. The creep test was performed for 15minutes under the maximum load of each step in order to understand the load-transfer property of permanent anchor and to decide which anchor to choose. The destruction range of soil due to the changes in load was estimated by installing dial gauge on the ground which was cast into the weathered rock. Ultimately, the study on the behavior of the anchor case into the weathered rock was performed by comparing and analyzing the estimated result of the UUC obtained by the full scale pull out test in the field with the exsting theoretical and practical results of soil and rock anchor.

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Centrifuge Model Experiments on Behaviors of Single Pile (단말뚝 거동에 관한 원심모형실험)

  • Yoo, Nam-Jae;Lee, Myeung-Woog;Lee, Jong-Ho
    • Journal of Industrial Technology
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    • v.17
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    • pp.111-118
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    • 1997
  • This thesis is an experimental research of investigating behavior of single pile, subjected to the vertical compression loads, using the centrifuge facility located in the geotechnical engineering laboratory in Kangwon National University. Centrifugal model experiments of model pile were carried out changing diameter of model pile, relative density of sandy ground and the gravitational level applied in the centrifuge. Thus, their effects on the load-settlement behavior and the ultimate bearing capacity of pile were investigated. Experimental results obtained from centrifuge model tests were compared with the theoretical or semi-empirical equations to analyze values of ultimate bearing capacity of model pile. When we compare the ultimate bearing capacity of experimental results with the ultimate bearing capacity of theorical results, the experimental results appear more higher in the De Beer method and Meyerhof. Expecially, Terzaghi method is very same as the experimental results normally.

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Ultimate and Fatigue Strength of Ship Hopper Knuckles (선체 호퍼너클 구조의 최종강도 및 피로강도)

  • 김영한;정장영;백점기;김하수;김도현
    • Journal of Welding and Joining
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    • v.18 no.1
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    • pp.77-82
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    • 2000
  • The aim of the present study is to investigate the characteristics of ultimate the fatigue strength of hopper knuckles in merchant vessels carrying bulk cargo or LNG/LPG/ The ultimate strength test is undertaken on the hopper knuckle model, subject to end tip load. A series of fatigue tests are carried out on the hopper knuckle models varying the level of the nominal stresses. The elasto-plastic finite element analysis is performed to examine the distribution of hot spot stresses near weld toe and also the progressive collapse behavior of the test model. S-N curves are developed based on the fatigue test results.

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Combined membrane and flexural reinforcement design in RC shells and ultimate behavior (막응력과 휨을 고려한 RC 쉘의 설계와 극한거동)

  • 민창식
    • Proceedings of the Korea Concrete Institute Conference
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    • 1998.10a
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    • pp.405-411
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    • 1998
  • An iterative numerical computational algorithm is presented to design a plate of shell element subjected to membrane and flexural forces. Based on equilibrium consideration, equations for capacities of top and bottom reinforcements in two orthogonal directions have been derived. The amount of reinforcement is determined locally, i. e., for each sampling point, from the equilibrium between applied and internal forces. One case of design is performed for a hyperbolic paraboloid saddle shell (originally used by Lin and Scordelis) to check the design strength against a consistent design load, therefore, to verify the adequacy of design practice for reinforced concrete shells. Based on nonlinear analyses performed, the analytically calculated ultimate load exceeded the design ultimate load from 14-43% for an analysis with relatively low to high tension stiffening, ${\gamma}$ =5~20 cases. For these cases, the design method gives a lower bound on the ultimate load with respect to Lower bound theorem. This shows the adequacy of the current practice at least for this saddle shell case studied. To generalize the conclusion many more designs-analyses are performed with different shell configurations.

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An Assessment on the Ultimate Strength of Welding Joint by the Effect of External Force (外力의 效果를 고려한 熔接部의 最終强度에 대한 評價)

  • Bang, Han-Seo;Cha, Yong-Hun;O, U-Seok
    • Journal of Ocean Engineering and Technology
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    • v.9 no.2
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    • pp.20-29
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    • 1995
  • When structures are constructed by welding, structural elements are always accompained by welding residual stress and deformation. Therefore, when the rigidity and strength of the welded structures is considered, it is very important to have sufficient information about the effect of initial deflection and welding residual stress on them. In this paper, the square plates with welding residual stress under compression are dealt with; First, heat conduction and thermal elastic-plastic problems are analyzed by finite element method using 4-node isoparametric elements for assessment on the ultimate strength of welding joint. Later, the ultimate strength of welding joint is assessed by examining the effect of changed type of loading. The specimens are 500{\times}$500mm(a/b=1) and 750{\times}$500mm(a/b=1.5) rectangular plates of whichthicknesses is 9.0mm and simply supported plates getting axiul load in each direction.

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Ultimate Strength Analysis of Ring-stiffened Cylinders with Initial Imperfections( I )

  • PARK CHI-MO;PARK DONG-MIN
    • Journal of Ocean Engineering and Technology
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    • v.17 no.5 s.54
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    • pp.48-56
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    • 2003
  • This paper has developed an efficient nonlinear finite element method that covers both initial deformations and initial stresses of general distribution in calculating the ultimate strength of ring-stiffened cylinders. The developed method and two widely-used commercial codes (NASTRAN and ABAQUS) were simultaneously applied to the same analysis model within the extent of those commercial codes' coverage to check the validity of the present method. After the validity check, it was used for parametric studies for more general cases of initial stress distribution, which produced some useful information about the imperfection sensitivity of the ultimate strength of ring-stiffened cylinders.

Ultimate Bearing Capacity of Strip Foundation on Geogrid -Reinforced Clayey Soil

  • Shin, Eun-Chul;Choi, Chan-Yong
    • Geotechnical Engineering
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    • v.13 no.3
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    • pp.77-86
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    • 1997
  • Laboratory model test results for the ultimate bearing capacity of a surface strip foundation supported by a near-saturated clayey soil reinforced with layers of geogrid have been presented. The optimum values for the width of the reinforcement layers, the depth of reinforcement, and the location of the first layer of geogrid for mobilization of maximum bearing capacity have been determined. Based on the model test results, an empirical procedure to estimate the ultimate bearing capacity has been developed.

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Ultimate Strength of Composite Laminates with Free-Edge Delamination (자유단 충간분리를 갖는 복합재 적층판의 최종 파괴강도)

  • 양광영;윤성운;김재열
    • Transactions of the Korean Society of Machine Tool Engineers
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    • v.11 no.2
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    • pp.59-64
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    • 2002
  • This paper presets experimental and analytical studies of ultimate strength of [$[30_2/-30_2/90]_S$ carbon/epoxy laminates with free-edge delamination under uniaxial tension. We performed tensile teat far laminates with Telflon inserted on interfaces to simulate initial free-edge delamination, The experiment reveals that extensional stiffness of the laminate decreases by the initiation of the delamination, and that strength of the laminate without delamination is smaller than that of the laminates with delamination. Generalized quasi-three delamination finite element analysis, which employs energy release rate and maximum stress criteria, predicts the ultimate strength of the laminates with sufficient accuracy.

An Experimental Study on the Shear Behavior of High Strength Concrete Deep Beam (고강도 철근 콘크리트 깊은 보의 전단거동에 관한 실험적 연구)

  • 함영삼;양근혁;이영호;정헌수
    • Proceedings of the Korea Concrete Institute Conference
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    • 2001.11a
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    • pp.897-902
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    • 2001
  • The purpose of this experimental study is to investigate the shear behavior of high-strength concrete deep beam and to grasp the conservatism of ACI Building Code. Experimental results on 12 deep beams under two equal symmetrically placed point loads are reported. Main variables are vertical and horizontal web reinforcement and shear span-to-overall depth ratio. Test results indicated that web reinforcement dose not affect on formation of inclined cracks but shear span-to-overall depth ratio affect on inclined shear cracks and ultimate shear strength. Addition of vertical web reinforcement improves ultimate shear strength of H.S.C. deep beams that shear span-to-overall depth ratio is 1.0. Considerable increase in ultimate shear strength of H.S.C. deep beams with increasing horizontal web reinforcement that shear span-to-overall depth ratio is 0.5. Especially with increasing concrete strength($f_{ck}$) the ACI code is conservative in estamating the ultimate shear strength of deep beams.

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Closed form ultimate strength of multi-rectangle reinforced concrete sections under axial load and biaxial bending

  • da Silva, V. Dias;Barros, M.H.F.M.;Julio, E.N.B.S.;Ferreira, C.C.
    • Computers and Concrete
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    • v.6 no.6
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    • pp.505-521
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    • 2009
  • The analysis of prismatic members made of reinforced concrete under inclined bending, especially the computation of ultimate loads, is a pronounced non-linear problem which is frequently solved by discretizing the stress distribution in the cross-section using interpolation functions. In the approach described in the present contribution the exact analytical stress distribution is used instead. The obtained expressions are integrated by means of a symbolic manipulation package and automatically converted to optimized Fortran code. The direct problem-computation of ultimate internal forces given the position of the neutral axis-is first described. Subsequently, two kinds of inverse problem are treated: the computation of rupture envelops and the dimensioning of reinforcement, given design internal forces. An iterative Newton-Raphson procedure is used. Examples are presented.