• Journal of the Society of Naval Architects of Korea
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• v.29 no.1
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• pp.103-112
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• 1992

The ultimate bending moment of ships is one of the principle strength considered in ship design. Several methods have been proposed to predict the ultimate bending moment and its major part is, in general, predicting the ultimate compressive strength of stiffened panels. In this paper, made is the review on the methods and formulae of predicting the ultimate compressive strength and they are applied to predicting the ultimate bending moment. Safely levels of three bulk carriers have been derived evaluated for two loading conditions, stray, light ship condition and full load condition, and wave bending by Classification Society Rule(ABS, DnV and Lloyd Rule). The present reliability analysis problem is strictly non-linear and the Advanced First-Order Reliability Method has been used. From the results of parametric studies, the methods of predicting the ultimate compressive strength of stiffened panels are compared from the view point of their applicability to the reliability assessment of ships structures. The paper ends wish a brief discussion drawn from the parametric studies and the extension of the study is described.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.24 no.3
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• pp.343-351
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• 2011

Nuclear containment building is the last barrier for being secure from any nuclear power plant accident. Therefore, it is very important to understand the ultimate capacity of nuclear containment building to loads associated with severe accidents. LOCA (loss of coolant accident) is considered as the basic accidental load and CANDU-type containment building is considered as a target structure in order to conduct the numerical analysis for the structural safety of a containment building. The CANDU-type containment building is a prestressed concrete shell structure which has the dome and the cylindrical wall and is reinforced with bonded tendons. In this paper, the evaluation of ultimate internal pressure capacity was carried out by nonlinear analysis of a prestressed concrete containment building using 3-dimensional structural analysis system.

• Journal of Korean Association for Spatial Structures
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• v.7 no.6
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• pp.69-74
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• 2007

Recently, to improve performance and strength of circular steel columns, application of concrete-filled steel tube(CFT) type are gradually increased. To accurately predict the plastic design of concrete-filled steel tube columns, a plasticity model is required which can be describe large deformation behavior of concretes and steels. In this study, elastic-plastic large deformation analysis is developed by using the plasticity model of structural steels, and accurate and validity of the developed program is verified by comparing between the experiment and the analysis for concrete-filled steel tube column. In concrete-filled steel tube columns, influence of initial deflection on ultimate strength behavior is investigated by using developed program.

• Structural Engineering and Mechanics
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• v.27 no.6
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• pp.697-711
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• 2007

Though extensive research has been carried out for the ultimate strength of steel reinforced concrete (SRC) members under static and cyclic load, there was only limited information on the applied analysis models. Modeling of the inelastic response of SRC members can be accomplished by using a microcosmic model. However, generally used microcosmic model, which usually contains a group of parameters, is too complicated to apply in the nonlinear structural computation for large whole buildings. The intent of this paper is to develop an effective modeling approach for the reliable prediction of the inelastic response of SRC columns. Firstly, five SRC columns were tested under cyclic static load and constant axial force. Based on the experimental results, normalized trilinear skeleton curves were then put forward. Theoretical equation of normalizing point (ultimate strength point) was built up according to the load-bearing mechanism of RC columns and verified by the 5 specimens in this test and 14 SRC columns from parallel tests. Since no obvious strength deterioration and pinch effect were observed from the load-displacement curve, hysteresis rule considering only stiffness degradation was proposed through regression analysis. Compared with the experimental results, the applied analysis model is so reasonable to capture the overall cyclic response of SRC columns that it can be easily used in both static and dynamic analysis of the whole SRC structural systems.

• Journal of the Society of Naval Architects of Korea
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• v.28 no.1
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• pp.189-196
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• 1991

This paper is an illustration of the application of the reliability analysis to the transverse structure of a SWATH ship. The ultimate strength of plate members on the cross structure and upper part of strut are considered in the reliability analysis. The fatigue reliability analysis has been also carried out at the junction of cross structure, sponsors and strut. Included is also an example of the allowable fatigue damage level. Demonstrated is the reliability study of series system of which elements are the ultimate and fatigue failure as well. Doing this would be desirable to get a truer solution of the structural safety level. The paper ends with a brief summary of the present reliability study and same important points which may be useful at the design stage.

• Journal of the Society of Naval Architects of Korea
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• v.43 no.2 s.146
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• pp.197-205
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• 2006

In general, brackets found at tank boundary are design according to the Classification Society Rule. Since much man power is needed in manufacturing the brackets stiffened by flange, it is necessary to suggest alternative designs, of which flanges are removed, through the rigorous structural analysis. In this paper non-linear structural analysis for brackets with and/or without flange have been carried out to examine their structural behavior and ultimate strengths. Alternative designs for brackets are suggested based on the results of ultimate strength analysis so that the alternative brackets have the similar level of strength and stiffness to the original brackets. It has been seen that the structural safety of alternative brackets proposed in this paper are beyond the appropriate level. The primary benefit of replacing the original brackets by the alternatives is the reduction of man power in manufacturing brackets and 10 to 15% weight saving can be expected in additional. This paper ends with some comments about the extension of the present study.

• International journal of steel structures
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• v.18 no.4
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• pp.1139-1152
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• 2018

Many studies on the application of stainless steels as structural materials in buildings and infra-structures have been performed thanks to superior characteristics of corrosion resistance, fire resistance and aesthetic appeal. Experimental investigation to estimate the ultimate strength and fracture mode of the fillet-welded connections of cold-formed austenitic stainless steel (STS304L) with better intergranular corrosion resistance than that of austenitic stainless steel, STS304 commonly used has carried out by authors. Specimens were fabricated to fail by base metal fracture not weld metal fracture with main variables of weld lengths according to loading direction. All specimens showed a block shear fracture mode. In this paper, finite element analysis model was developed to predict the ultimate behaviors of welded connection and its validity was verified through the comparison with test results. Since the block shear behavior of welded connection due to stress triaxiality and shear-lag effects is different from that of bolted connection, stress and strain distributions in the critical path of tensile and shear fracture section were investigated. Test and analysis strengths were compared with those by current design specifications such as AISC, EC3 and existing researcher's proposed equations. In addition, through parametric analysis with extended variables, the conditions of end distance and longitudinal weld length for block shear fracture and tensile fracture were suggested.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.20 no.5
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• pp.96-102
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• 2021

Hexagonal bolt, nut, fittings, and high-pressure valves with special alloy play an important role in many industrial products. Numerical analysis was conducted to obtain data for designing a new drawing system. This study aims to predict the rolling force of the new drawing system compared to that of the established drawing system. The rolling force of the new drawing system was predicted using numerical analysis by assuming that it is in proportion to deformation. The rolling forces of Mo, Ti, and W were approximately 1.4, 0.5, and 2.5 times those of SUS. Because the values of ultimate strength of special alloys were more close to numerical analysis, the values of ultimate strength could be used to predict the rolling force of the new drawing system without numerical analysis in field.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.4
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• pp.1337-1347
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• 2013

The parametric analysis on ultimate behavior of buried cylindrical GFRP(Glass Fiber Reinforced Polymer) septic tank was presented. Two kinds of F.E. analysis model(soil-spring model and 3D full model) was constructed. The ultimate behavior of septic tank was investigated according to the size of stiffened steel ring and properties of underground soil. Ramberg-Osgood model and Druker-Prager model were used for material nonlinear characteristics of GFRP septic tank and soil, respectively. The diameter and thickness of stiffened steel ring inside septic tank, elastic modulus and internal friction angle of soil were selected for parametric variables. The ultimate behavior of septic tank, load-displacement, axial and hoop strain, were calculated and investigated.

• Proceedings of KOSOMES biannual meeting
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• 2004.11a
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• pp.137-141
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• 2004

Ship structures are basically an assembly of plate elements and the load-carrying capacity or the ultimate strength is one of the most important criteria for safety assessment and economic design. Also, Structural elements making up ship plated structures do not work separately, resulting in high degree of redundancy and complexity, in contrast to those of steel framed structures. To enable the behavior of such structures to be analyzed, simplifications or idealizations must essentially be made considering the accuracy needed and the degree of complexity of the analysis to be used. On this study, to investigate effect of modeling range, the finite element method are used and their results are compared varying the analysis ranges. The model has been selected from bottom panels of large merchant ship structures. For FEA, three types of structural modeling are adopted in terms of the extent of the analysis. The purpose of the present study is to numerically calculate the characteristics of ultimate strength behavior according to the analysis ranges of stiffened panels subject to uniaxial compressive loads.