• Steel and Composite Structures
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• v.24 no.5
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• pp.549-559
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• 2017

As few multi-tower single-box multi-cell cable-stayed bridges with corrugated steel webs have been built, analysis is mostly achieved by combining single-girder model, beam grillage model and solid model in support of the design. However, such analysis methods usually suffer from major limitations in terms of the engineering applications: single-girder model fails to account for spatial effect such as shear lag effect of the box girder and the relevant effective girder width and eccentric load coefficient; owing to the approximation in the principle equivalence, the plane grillage model cannot accurately capture shear stress distribution and local stress state in both top and bottom flange of composite box girder; and solid model is difficult to be practically combined with the overall calculation. The usual effective width method fails to provide a uniform and accurate "effective length" (and the codes fail to provide a unified design approach at those circumstance) considering different shear lag effects resulting from dead load, prestress and cable tension in the construction. Therefore, a novel spatial grid model has been developed to account for shear lag effect. The theoretical principle of the proposed spatial grid model has been elaborated along with the relevant illustrations of modeling parameters of composite box girder with corrugated steel webs. Then typical transverse and longitudinal shear lag coefficient distribution pattern at the side-span and mid-span key cross sections have been analyzed and summarized to provide reference for similar bridges. The effectiveness and accuracy of spatial grid analysis methods has been finally validated through a practical cable-stayed bridge.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.39 no.2 s.120
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• pp.54-59
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• 2007

Cereal, computer software, wine, small appliances, and fast foods are examples of products that have switched from folding carton to microflute corrugated paperboard. Microflute corrugated paperboards have their unique wonderful packaging characteristics that are driving forces for people to use more and more. Good strength property, excellent shock absorbing ability, and beautiful outer appearance of microflute corrugated paperboards go hand and hand with their environmental advantages. It is known that physical properties of microflute corrugated paperboards depend on not only properties of base paper but corrugator operating conditions. This study was carried out to investigate on the corrugator's optimum operating conditions for making micro flute corrugated paperboards. Lab-scaled micro flute corrugator was installed and run with systematic changes of operation conditions to investigate the effects of operation conditions on physical properties of micro flute corrugated paperboards.

• Food Science and Preservation
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• v.8 no.4
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• pp.345-350
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• 2001

This study was measured weight loss, total ascorbic acid, titratable acidity, and soluble solids content to investigate the effect of EPS(expanded polystyrene foam, foaming rate 55 times V/W) box, LDPE film pouches and double wall corrugated fiberboard box during storage at 20$\^{C}$. Weight loss of apple packed with corrugated paperboard box after 40 days storage was 5.7%, arid those of LDPE, CE(zeolited coated film) film and EPS box were 0.2-0.5%. Ascorbic acid content of apple packed with LDPE, CE, EPS was higher than that of control. Titratable acidity and total soluble solid content of control were changed 40% and 10%, but the EPS were changed 27% and 4%, respectively. Overall appearances of ‘Fuji’apple packed with LDPE, CE and EPS were better than that of control.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.13 no.1
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• pp.5-8
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• 2007

The effects of packaging conditions on freshness extension of cucumber were investigated during 24-day storage temperatures $18^{\circ}C$ and $10^{\circ}C$. The storage life of cucumbers was influenced by both packaging methods (corrugated cardboard vs EPS box) and temperatures during storage. The fresh weigh, vitamin C content and Chlorophyll of cucumbers were decreased, while yellowing of cucumber peel was increased during storage. The change of vitamin C content was influenced by both packaging method and temperature during storage. The EPS box and low temperature were revealed to be effective treatments to extend the storability or cucumber fruit.

• Structural Engineering and Mechanics
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• v.50 no.4
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• pp.501-524
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• 2014

This paper presents a type of composite box girder with corrugated webs and concrete filled steel tube slab to overcome cracking on the web and reduce self-weight. Utilizing corrugated steel web improves the efficiency of prestressing introduced into the top and bottom slabs due to the accordion effect. In order to understand the loading capacity of such new composite structure, experimental and numerical analyses were conducted. A full-scale model was loaded monotonically to investigate the deflection, strain distribution, loading capacity and stiffness during the whole process. The experimental results show that test specimen has enough loading capacity and ductility. Based on experimental works, a finite element (FE) model was established. The load-displacement curves and stress distribution predicted by FE model agree well with that obtained from experiments, which demonstrates the accuracy of proposed FE model. Moreover, simplified theoretical analysis was conducted depending on the assumptions which were confirmed by the experimental and numerical results. The simplified analysis results are identical with the tested and numerical results, which indicate that simplified analytical model can be used to predict the loading capacity of such composite girder accurately. All the findings of present study may provide reference for the application of such structure in bridge construction.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2007.11a
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• pp.223-229
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• 2007

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.1
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• pp.76-79
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• 2000

The effects of packaging conditions on freshness extension of squash (Cucurbita moscata) were investigated during 7-day storage at 2$0^{\circ}C$. Weight loss of squash packed with corrugated paperboard box (control) was 5.5%, and those of LDPE (low density polyethylene, Ф0.02 mm), LDPE (Ф0.04mm) film and EPS (expanded polystyrene) box were 0.9%, 0.8%, and 1.1%, respectively. Firmness of EPS was 11% higher than that of control, chlorophill content of squash packed with EPS box was 18.9% higher, and total ascorbic acid content of squash packed with EPS box was 29.4% higher than that of control. Quality of packed squash was not different between EPS packages and LDPE packages. Decay of control was 1~2 pieces per box, but was not found in the LDPE, EPS box. Preferences in overall appearences of LDPE, EPS box was better than those of control.

• The monthly packaging world
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• s.148
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• pp.99-103
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• 2005

• The monthly packaging world
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• s.254
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• pp.45-49
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• 2014

• The monthly packaging world
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• s.113
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• pp.74-81
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• 2002