• Proceedings of the Computational Structural Engineering Institute Conference
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• 2002.04a
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• pp.35-42
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• 2002

In this paper, effective analysis of beam is studied using the RKPM in meshless methods. So, RKPM is extended for solving moderately thick and thin beam. General Timoshenko beam theory is used for formulation. Shear locking is the main difficulty in analysis of beam structures. The shear relaxation factor and corrected shear rigidity are introduced to overcome shear locking. Analysis results obtained reveal that RKPM using introduced methods Is free of locking and very effectively applicable to deeply as well as shallowly beams.

• Fashion & Textile Research Journal
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• v.8 no.3
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• pp.357-362
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• 2006

This study is to evaluate the objective sensibility of the commercial lining fabrics. Five kinds of the linings were collected by adding taffetas with four kinds of fibers (polyester, nylon, rayon, and acetate) to one polyester stretch fabric. The six basic mechanical and hand properties were studied by using KES-FB system (Kawabata Evaluation System). The result of measuring the mechanical properties shows that polyester has high bending rigidity (B), that polyester-stretch has a high value of linearity of load-extension curve (LT), tensile energy (WT), tensile resilience (RT), and coefficient of friction (MIU) and a low value of bending rigidity(B), shear property, and geometrical roughness (SMD). The nylon has a high value of bending rigidity (B), shear property, and compression resilience (RC). The rayon has a high value of coefficient of friction (MIU) and linearity of compression-thickness curve (LC) and a low value of shear property, and the acetate has a low value of shear property. The result of hand value shows that polyester, nylon, and acetate are a high value of KOSHI (stiffness), NUMERI (smoothness), and FUKURAM (fullness & softness), and they feel stiff and massive, that rayon has a low value of NUMERI and FUKURAMI. The total result of hand value shows that polyester taffeta and polyester stretch fabric are about the same as the best material for the lining of a woman's dress for spring and summer, and the next thing is acetate, but nylon and rayon are somewhat inferior materials. This provides a fundamental data for the comfortable clothing production of a higher value-added product through the study on the mechanical and hand properties of the lining as well as the right side of fabrics.

• Journal of the Korean Society of Clothing and Textiles
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• v.25 no.3
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• pp.650-661
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• 2001

The purpose of this study is to suggest a guidance to select proper muslin through investigating fabric characteristics. The structural and physical properties of muslin and top fabric samples were tested by KES-FB system and other testers. And in order to examine the relation between fabric characteristics and the shape of garments, wearing tests were done with jackets made of those samples. As a result, bending rigidity(B), bending hysteresis(2HB), shear stiffness(G), shear hysteresis at=0.5(2HG), shear hysteresis at=5(2HG5), stiffness, cloth count/5cm, weight, thickness were extracted as the key factors affecting the appearance of garments. To have similar appearance, all of these should be counted. After standardizing, we calculate the variance between top cloth and muslin. And from this we could get the range that the proper muslin should be included. The ranges were as follows: Bending rigidity(B): within 0.024g.$\textrm{cm}^2$/cm(0.3$\sigma$); Shear stiffness(G): within 2.21g/cm.degree(1.3$\sigma$) Weight: within 9.33mg/$\textrm{cm}^2$(18$\sigma$); Thickness: within 0.20mm(1.8$\sigma$)

• Bulletin of the Society of Naval Architects of Korea
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• v.22 no.1
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• pp.45-53
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• 1985

For the analysis of vertical vibrations of a ship's hull, the Timoshenko beam analogy is accepted up to seven or eight-node modes provided that the system parameters are properly calculated. As to the shear coefficient, it has been a common practice to apply the strain energy method or the projected area method. The theoretical objection to the former is that it ignores lateral contraction due to Poisson's ratio, and the latter is of extreme simplifications. Recently, Cowper's and Stephen's shear coefficient formulas have drawn ship vibration analysts' attentions because these formulas, derivation of which are based on an integrations of the equations of three-dimensional elasticity, take Poisson's ratio into account. Providing computer programs for calculation of the shear coefficient of ship sections modeled as thin-walked multicell sections by each of the forementioned methods, the authors calculated natural vibration characteristics of a bulk carrier and of a container ship by the transfer matrix method using shear coefficients obtained by each of the methods, and discussed the results in comparision. The major conclusions resulted from this investigation are as follows: (1) The shear coefficients taking account of the effects of Poisson's ratio, Cowper's $K_c$ and Stephen's $K_s$, result in higher values of about 10% in maximum as compared with the shear coefficient $K_o$ based on the conventional strain energy methods; (a) $K_c/K_o{\cong}1.05\;and\;K_s/K_o{\cong}1.10$ for ships having single skin side-shell such as a bulk carrier. (b) $K_c/K_o{\cong}1.02\;and\;K_s/K_o{\cong}1.05$ for ships having longitudinally through bulkheads and/or double side-shells in the portion of the cargo hod such as a container carrier. (2) The distributions of the effective shear area along the ship's hull based on each of $K_o,\;K_c\;and\;K_s$ are similar each another except the both end portions. (3) Natural frequencies and mode shapes of the hull based on each of $K_c\;and\;K_s$ are of small differences as compared each other. (4) In cases of using $K_c\;or\;K_s$ in ship vibration analysis, it is also desirable to have the bending rigidity be corrected according to the effective breadth concept. And then, natural frequencies and mode shapes calculated with the bending rigidity corrected in the above and with each of $K_o,\;K_c\;and\;K_s$ result in small differences as compared each another. (5) Referring to those mentioned in the above (3) and (4) and to the full-scale experimental results reported by Asmussen et al.[17], and considering laboursome to prepare the computer input data, the following suggestions can safely be made; (a) Use of $K_o$ in ship vibration analysis is appropriate in practical senses. (b) Use of $K_c$ is appropriate even for detailed vibration analysis of a ship's hull. (6) The effective shear area based on the projected area method is acceptable for the two-node mode.

• Textile Coloration and Finishing
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• v.12 no.3
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• pp.159-165
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• 2000

This study surveys the fabric mechanical properties according to the weaving design & finishing conditions of wool fabrics for quality control in the process. For this purpose, 8 kinds of Twill groups and 3 kinds of Plain groups weave fabrics, totally 428 woven fabrics are prepared with change of the yarn count, density and finishing method. Fabric thickness, bending rigidity, extensibility, shear rigidity, formability of the fabrics were measured and discussed with weaving design & finishing conditions.

• Interaction and multiscale mechanics
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• v.6 no.3
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• pp.287-300
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• 2013

In this paper, the effect of impulsive line on the propagation of shear waves in non-homogeneous elastic layer is investigated. The rigidity and density in the intermediate layer is assumed to vary quadratic as functions of depth. The dispersion equation is obtained by using the Fourier transform and Green's function technique. The study ends with the mathematical calculations for transmitted wave in the layer. These equations are in complete agreement with the classical results when the non-homogeneity parameters are neglected. Various curves are plotted to show the effects of non-homogeneities on shear waves in the intermediate layer.

• International Journal of Safety
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• v.9 no.1
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• pp.21-29
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• 2010

When a new member of a scaffold is developed, it is necessary to follow the standard. Therefore, all scaffolds will assume the same structure. The aim of this study was to establish a new method for evaluating scaffold performance. In the present study, a buckling analysis of prefabricated scaffolds was executed, using the shear rigidity of the vertical and the horizontal frames as parameters. From the results, an equation is proposed for evaluating the strength of prefabricated scaffolds.

• Journal of Fashion Business
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• v.7 no.6
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• pp.50-56
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• 2003

Chitosan has been widely applied to the products in various industries such as textile fabrics, apparels, foods, medical area, etc. Cochineal has long been employed as one of natural dyestuffs in the textile industry. The effect of chitosan pre-treatment on the low-stress physical and mechanical properties of cochineal-dyed fabrics including cotton, silk, nylon and polyester fabrics was investigated in this study. The chitosan treatment and mordanting of the fabrics changed the bending, shear, compression, and surface properties of the fabrics. In cotton fabric specimens, while the increase of B(bending rigidity) of cotton is relatively high, the increase of G(shear rigidity) of cotton is relatively low. In nylon and PET fabric specimens, while the increase tendency of B is relatively low, that of G is high compared to the corresponding cotton fabrics.

• Computers and Concrete
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• v.13 no.2
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• pp.271-290
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• 2014

In this study, structural irregularities in plan, which has a considerable effect on earthquake behavior of buildings, have been investigated in detail based on Turkish Earthquake Code 2007. The study consists of six main parametric models and a total of 144 sub-models that are grouped based on RC structural systems such as frame, frame + rigid core, frame with shear wall, and frame with shear wall + rigid core. All models are designed to have both symmetrical plan geometry and regular rigidity distribution. Changes in the earthquake behavior of buildings were evaluated according to the number of storeys, number of axes and the configuration of structural elements. Many findings are obtained and assessed as a result of the analysis for each structural irregularity. The study shows that structural irregularities can be observed in completely symmetric buildings in terms of plan geometry and rigidity distribution.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.05a
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• pp.399-400
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• 2023

Current building structural standards require the shear strength and rigidity in the design of vertical construction joints in a slurry wall. This paper proposes a shear key resistance method for shear connection of vertical construction joints, and compares its structural performance with the currently prevalent method of shear friction rebar. The study found the structural performance of the shear key resistance method was significantly better than that of the shear friction rebar method.