• Proceedings of the Computational Structural Engineering Institute Conference
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• 1993.10a
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• pp.74-78
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• 1993

Compared with rigid-jointed latticed dome, in pinned-joint latticed dome, results of Ref.1 showed reduction of buckling strength by decline of junction's rotational rigidity. Moreover, with decline of junction's rotational rigidity, geometrical initial imperfection incurs more and more reduction of buckling-strength. This study, subsequently the case of rigid-joint domes, is aimed at analyzing buckling-characteristics of pinned-joint single-layer latticed domes with triangular network subjected to initial imperfection.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.1C
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• pp.41-51
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• 2008

The load distribution and deformation of single piles which is embedded in Jumunjin sand and Kimhae clay are investigated, based on small scale model tests. Special attention is given to the consideration of flexural rigidity in laterally loaded piles. To consider the flexural rigidity of the pile, tests are performed with the aluminium piles of three different length under different relative densities and undrained shear strength. The test results indicate that the initial slope from the results of tests is proportional to the depth and pile-soil rigidity in both soils. But the increasing rate of the initial slope in the clay is less than in the sand. In addition, the soil resistance is more related to the depth and soil condition than the pile rigidity. Base on the test results, an empirical formula is proposed, which is good agreement with previously published small scale model test and field lateral load test.

• Earthquakes and Structures
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• v.9 no.4
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• pp.753-766
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• 2015

An investigation has been carried out for the propagation of torsional surface waves in an inhomogeneous prestressed layer over an inhomogeneous half space when the upper boundary plane is assumed to be rigid. The inhomogeneity in density, initial stress (tensile and compressional) and rigidity are taken as an arbitrary function of depth, where as for the elastic half space, the inhomogeneity in density and rigidity is hyperbolic function of depth. In the absence of heterogeneities of medium, the results obtained are in agreement with the same results obtained by other relevant researchers. Numerically, it is observed that the velocity of torsional wave changes remarkably with the presence of inhomogeneity parameter of the layer. Curves are compared with the corresponding curve of standard classical elastic case. The results may be useful to understand the nature of seismic wave propagation in geophysical applications.

• Fashion & Textile Research Journal
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• v.9 no.3
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• pp.347-350
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• 2007

To analyse basic properties for making packing batt according to doubling condition, packing batt yarn, of $300^D$, $900^D$, $3600^D$ made from DTY yarn $150^D$/48 were produced from KTDI. The results are as follows: The birefringence of the sample yarn increased with increasing the annealing temperature and denier. The initial modulus of the sample yarn decreased with increasing the annealing temperature and denier. The higher than annealing temperature of $160^{\circ}C$, initial modulus of the sample are equilibrated. The strain recovery ratio of samples decreased with increasing the annealing temperature and denier. The lower than annealing temperature of $140^{\circ}C$, strain recovery ratio of the sample are decreased Where the $900^D$, $3600^D$ yarns are at $100^{\circ}C$ the specific bending rigidity value obtained is 0.65kgf/d but the twisted yarn (3,600) obtained 0.006 ($gfcm^2/tex^2$). However, where the heat temperature is $160^{\circ}C$, specific bending rigidity value obtained 0.003($gfcm^2/tex^2$).

• Journal of Korean Association for Spatial Structures
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• v.14 no.3
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• pp.47-56
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• 2014

This paper investigates the characteristics of unstable behaviour and critical buckling load by joint rigidity of framed large spatial structures which are sensitive to initial conditions. To distinguish the stable from the unstable, a singular point on equilibrium path and a critical buckling level are computed by the eigenvalues and determinants of the tangential stiffness matrix. For the case study, a two-free node example and a folded plate typed long span example with 325 nodes are adopted, and these adopted examples' nonlinear analysis and unstable characteristics are analyzed. The numerical results in the case of the two-free node example indicate that as the influence of snap-through is bigger; that of bifurcation buckling is lower than that of the joint rigidity as the influence of snap-through is lower. Besides, when the rigidity decreases, the critical buckling load ratio increases. These results are similar to those of the folded-typed long span example. When the buckling load ratio is 0.6 or less, the rigidity greatly increases.

• Steel and Composite Structures
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• v.6 no.6
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• pp.493-512
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• 2006

The present paper summarizes the experimental research carried out at the "Politehnica" University of Timisoara, Romania, with the scope of investigating the influence of different column web stiffening solutions on the performance of beam-to-column joints of Moment Resisting Steel Frames. The response parameters, such as resistance, rigidity and ductility were examined. Five different types of panel web stiffening were compared with regard to a reference test. A quasi-linear relationship between the moment capacity and the total shear area of the web panel was observed from the experimental tests while the initial rigidity increased non-proportionally with the same area. Comparisons are presented of the experimental tests with the mathematical model developed by Krawinkler and with the model stipulated in Eurocode 3 Part 1.8. These comparisons showed a generally good agreement in the case of moment capacity, while the computed rigidities were always greater than the experimental rigidities.

• Journal of the Korean Society of Marine Environment & Safety
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• v.20 no.6
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• pp.738-745
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• 2014

In this paper, It is performing to the elastic and elasto-plastic large deformation series analysis using a numerical method for the initial deflection effect of the aluminum alloy rectangular plate in the elasto-plastic loading area patch loading size. It is assumed a boundary condition to be a simply supported condition and consider the initial deflection amplitude, aspect ratio. It examined the critical elastic buckling load and post-buckling behaviour of aluminium alloy A6082-T6 rectangular plate. It used a commercial program for the elastic and elasto-plastic deformation series analysis. If the initial deflection amplitude is smaller, the in-plane rigidity with increasing to load is reduced from the start and occurs significantly more increasing the amplitude. More higher the aspect ratio, the initial yield strength is gradually decreased, and the plate thickness thicker and occurs larger than the thin walled plate a reduction ratio of the initial yield strength of the patch loading size as 0.5.

• Journal of Korean Association for Spatial Structures
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• v.13 no.1
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• pp.87-96
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• 2013

This study investigated characteristics of buckling load and effective buckling length by member rigidity of dome-typed space frame which was sensitive to initial conditions. A critical point and a buckling load were computed by analyzing the eigenvalues and determinants of the tangential stiffness matrix. The hexagonal pyramid model and star dome were selected for the case study in order to examine the nodal buckling and member buckling in accordance with member rigidity. From the numerical results, an effective buckling length factor of adopted models was bigger than that of Euler buckling for the case of fixed boundary. These numerical models indicated that the influence of nodal buckling was greater than that of member buckling as member rigidity was higher. Besides, there was a tendency that the bifurcation appeared on the equilibrium path before limit point in the member buckling model.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2002.11a
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• pp.107-112
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• 2002

Basically, ship structure consists of the plate members, and a strength of overall ship structurnds on the stiffness and strength of ship platings. If buckling which causes to deflect ship plate members occurs, the stiffness of ship plate markedly decreases, and thus buckling has a serious effect on the stiffness or strength of overall ship structure. Buckling is one of the most important design criteria when we scantle structure members. In the present study, a inplane rigidity of a compressed ship plate above buckling load is proposed. The proposed inplane rigidity is available in the elastic or elasto-Plastic ranges in order to can out a more efficient and reliable design.

• Textile Coloration and Finishing
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• v.18 no.2 s.87
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• pp.39-45
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• 2006

The aim of this work is to develop sense-differentiated textiles using Thick-Thin polyester yarn(T-T yarn) with finer than 1 denier mono filament. The ITY(Interlace Textured Yarn) using T-T yarn with various over feed ratios of PET filament was manufactured with different shrinking percentage of core yarn and then the fabrics were woven on the same weaving 100m using ITY produced. The mechanical properties and the handles of the fabrics were examined with KES-FB system suggested by Kawabata. The shrinkage of ITY was increased with decreasing over feed ratio and increased with increasing heat treatment temperature of T-T yarn. The initial elasticity modulus of ITY was decreased with increasing over feed ratio and heat treatment temperature of T-T yarn. The tensile energy of fabrics was decreased with increasing of over feed ratio, but bending rigidity and shear rigidity of fabrics were increased with increasing of over feed ratio of PET filament. The results indicate that the fabric using T-T yarn with finer than I denier mono filament can be used for the purpose of sense-differentiated textile.