• Journal of the Korean Society of Costume
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• v.53 no.5
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• pp.23-31
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• 2003

The Purpose of this study was to isolate and identify fungi found in excavated clothes dating on the 16th century. As a result of microscoping with LPCB staining, seven isolated strains were classified-Acremonium strictum, Acremonium kiliense, Fonsecaea sp., Candida sp., Trichoderma sp., Cladosporium spp., Penicillium spp.. In the process of isolation and identification of fungi by the sort of textile, more fungi were found in cotton, cotton batt and silk than in ramie and hemp, suggesting that hemp has antibacterial characteristics due to the presence of lignin. In the Comparison washed samples with unwashed ones, there were more kinds of fungi in washed samples. In the cellulase activity test, Acremonium kiliense had the highest level cellulase activity, suggesting that Acremonium killiense has an important Influence on damage of textiles.

• Journal of the Korea institute for structural maintenance and inspection
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• v.8 no.1
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• pp.139-146
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• 2004

In this paper, the seismic analysis and the modeling techniques have been introduced for seismic performances assessment, when seismic isolation bearings are applied to a real bridge. Nonlinear time-history analysis is carried out using finite element analysis program. El Centro earthquake(1940, N00W) used as earthquake ground excitations. The seismic response of seismically isolated bridge is compared with that of a bridge using conventional Pot Bearings, after obtaining the displacements of the deck, the deformations of the piers, shear forces and moments of the bottoms of the piers. The analytical analysis results show that seismic isolation bearing, especially seismic isolation bearings with sliding mechanism, could reduce earthquake forces.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.13 no.1
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• pp.13-24
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• 1993

The tangent stiffness matrices of the plane frame and the thin-walled space frame are derived by using the principle of virtual displacement. In case of the plane frame, the shape function and stiffness matrices are presented for the rigid-hinged condition. For the unsymmetric thin-walled space frame, the elastic and geometric stiffness matrices in three cases of the unrestrained torsion, the restrained torsion, and the restrained anti unrestrained torsion are evaluated by using the various Hermitian polynomials as the shape function. Numerical examples for the lateral buckling analysis of the space frames and the circular arch illustrate the accuracy and convergence characteristics of the derived formulations.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.12 no.3
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• pp.91-105
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• 1992

For the analysis of multistory frames with sidesway, no adequate procedures can be found in the classical methods of structural analysis. Even well-known procedures such as the slope-deflection method and the moment distribution method may not be effective tools since those methods require a multiple of computational labor and/or yield results of approximate values. In this study, a direct method is developed and proposed for the analysis of multistory frames with sidesway, which is due to the lateral loads, asymmetry of the structure itself, or asymmetry of vertical loadings. The proposed method is to obtain simple forms of equations derived by a mathematical formulation of the moment distribution procedure combined with successive correction concept. Numerical illustrations show that the results obtained by the proposed method agree well with those by rigorous ones. Undoubtedly, this newly developed method can be applied more easily for the analysis of structural frames without joint translation as well as continuous beams.

• Journal of Korean Society of Steel Construction
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• v.11 no.2 s.39
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• pp.109-116
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• 1999

This paper presents an experimental study on the behavior of CFT Column to H-Beam Endplate Connections with penetrated H/T bolts under monotonic loading. The object of this study is to estimate accurately the effect about the thickness of endplate and the arrangement of H/T bolts which was not got a grip on the results reported in the previous paper. Main parameters are the thickness of endplates (12mm, 16mm) and the arrangemement of H/T bolts (EP1, EP2, EP3 Type). The experimental results compared and analysed. 1) The specimens were classified by Bjorhovde's and EC3's method. 2) A formula to predict the ultimate moment of connection was derived based on the T-stub model, and theoretical value $(_tM_u)$ computed by the formula corresponded to the experimental value $(_eM_u)$.

• Journal of Korean Society of Steel Construction
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• v.19 no.2
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• pp.233-245
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• 2007

Previous finite element studies have shown that AASHTO Standard load distribution factor (LDF) equations appear to be conservative for longer spans and larger girder spacing, but too permissible for short spans and girder spacing. AASHTO LRFD specification defines the distribution factor equation for girder spacing, span length, slab thickness, and longitudinal stiffness. However, this equation requires an iterative procedure to correctly determine the LDF value due to an initially unknown longitudinal stiffness parameter. This study presents a simplified LDF equation for interior and exterior girders of two-span continuous I-girder bridges that does not require an iterative design procedure. The finite element method was used to investigate the effect of girder spacing, span length, slab thickness, slab width, and spacing and size of bracing. The computer program, GTSTRUDL, was used to idealize the bridge superstructures as the eccentric beam model, the concrete slab by quadrilateral shell elements, steel girders by space frame members, and the composite action between these elements by rigid links. The distribution factors obtained from these analyses were compared with those from the AASHTO Standard and LRFD methods. It was observed through the parametric studies that girder spacing, span length, and slab thickness were the dominant parameters compared with others. The LRFD distribution factor for the interior girder was found to be conservative in most cases, whereas the factor for the exterior girder to be unconservative in longer spans. Furthermore, a regression analysis was performed to develop simplified LDF formulas. The formulas developed in this study produced LDF values that are always conservative to those from the finite element method and are generally smaller than the LDF values obtained from the AASHTO LRFD specification. The proposed simplified equation will assist bridge engineers in predicting the actual LDF in two-span continuous I-girder bridges.