• Proceedings of the Korea Concrete Institute Conference
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• 2002.10a
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• pp.641-646
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• 2002

FRP-concrete composite slab is consisted of brittle materials and then shows brittle failure mechanism. This study suggests a new design approach that FRP-concrete composite slab leads to ductile failure, and investigates their failure behaviors for two types of section by numerical analysis. Box-type section is higher than I-type section in load capacity to required FRP quantity. Each section was designed so that the strain of FRP plate is 50% to its ultimate strain on initiation of concrete crushing, and it is verified that displacement ductility is more than two. Ductility capacity can be improved by reducing the strain of FRP on initiation of concrete crushing, but as the strain of FRP is reduced load capacity to required FRP quantity is also reduced. Therefore section optimization study is needed considering safety and economical efficiency.

• International Journal of Concrete Structures and Materials
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• v.9 no.2
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• pp.255-266
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• 2015

A strut-and-tie based method intended for determining the load-carrying capacity of reinforced concrete (RC) corbels is presented in this paper. In addition to the normal strut-and-tie force equilibrium requirements, the proposed model is based on secant stiffness formulation, incorporating strain compatibility and constitutive laws of cracked RC. The proposed method evaluates the load-carrying capacity as limited by the failure modes associated with nodal crushing, yielding of the longitudinal principal reinforcement, as well as crushing or splitting of the diagonal strut. Load-carrying capacity predictions obtained from the proposed analysis method are in a better agreement with corbel test results of a comprehensive database, comprising 455 test results, compiled from the available literature, than other existing models for corbels. This method is illustrated to provide more accurate estimates of behaviour and capacity than the shear-friction based approach implemented by the ACI 318-11, the strut-and-tie provisions in different codes (American, Australian, Canadian, Eurocode and New Zealand).

• Journal of Ocean Engineering and Technology
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• v.9 no.2
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• pp.156-166
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• 1995

Regrading the development of offshore natural gas field near Sakhalin Island which is an ice-infested area, this study aims to estimate the dynamic ice load for construction of offshore structures operating in this region. In this paper the design ice load and dynamic responses of a slender Arctic structure upon continuous ice movement are sutdied. Crushing agter a certain elastic deformation is assumed as a primary failure mechanism at the contact zone between semi-infinite level ice edge and the face of structure. Dynamic interaction forces are calculated using a modified Korzhavin's equation and a two-dimensional ice-structure interaction model is adopted. To verify the numerical model, dynamic analysis is performed for on of the Baltic Sea channel markers whose response patterns were presiously observed.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.11c
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• pp.803-810
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• 2000

Red pepper powder is produced from dried red pepper through milling process with roller mill. Traditional Roller mill is convenient for crushing wax and fiber parts in red pepper. However, some metallics are produced by the friction of two rollers when it operates without feeding of red peppers. In order to reduce this metallic problems created in the roller mill in the process of red pepper, a new roller mill mechanism which enables two roller to apart when red pepper is not fed between two rollers was introduced. Adjustment of clearance between two rollers was able to conducted by the current difference between idling and crushing process. Two types of roller surface, grove and flat, and two different roller mills, cast iron and Ti coating, are tested and compared in this experiment.

• Journal of the Korean Professional Engineers Association
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• v.33 no.5
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• pp.77-82
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• 2000

In this study, effect of freezing and cryogenic crushing on physico-chemical characteristics of sardine, pollack and sqiud representative for domestic frozen fishery products was investigated and some product using them was tried to be prepared. Dehead and viscerated, washed fishes were subjection to freezing without air circulation and liquid N2 gas at -20$\^{C}$,-40$\^{C}$ and -80$\^{C}$, and then frozen fishes were crushed by hammermill, masscolloider and the product was stored added with anti-freeze such as sorbitol, phosphates, starch and egg Powder, qualify of frozen squid surimi was not changes during 70 days at below -20$\^{C}$ . The results of quality characteristics and sensory evaluation of patties and nugget which made from shattered squid and pollack were similar to commercial products in flavor, color and texture, but sardine meat was inferior to commercial products in flavor and color.

• Transactions of the Korean Society of Automotive Engineers
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• v.2 no.1
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• pp.65-72
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• 1994

Collapse characteristics of thin-walled hatted section tubes are investigated. The square section members with flanges are substituted by the equivalent rectangular tube. The stiffening effects of flanges are transformed to the restraining plate with the equivalency of buckling strength. The square tubes of single-hatted and double-hatted sections are investigated. The double-hatted section members show symmetric and antisymmetric crushing modes depending on the stiffness of flanges. The single-hatted section members show only symmetric modes. The bifurcation point of the compact crushing modes are investigated by experiments and shown almost same thickness-width ratio of the rectangular tubes. A large maximum crippling strength can be obtained by double-hatted section members with proper flange dimensions.

• International Journal of Automotive Technology
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• v.7 no.5
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• pp.565-570
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• 2006

The development of a light-weight vehicle is in great demand for enhancement of fule efficiency and dynamic performance. The vehicle weight can be reduced effectively by using lightweight materials such as aluminum and magnesium. However, if such materials are used in vehicles, there are often instances when different materials such as aluminum and steel need to be joined to each other. The conventional joining method, namely resistance spot welding, cannot be used in joining different materials. Self-piercing rivet(SPR) and adhesive bonding, however, are good alternatives to resistance spot welding. This paper is concerned with the crushing test of double hat-shaped member made by resistance spot welding, SPR and adhesive bonding. Various parameters of crashworthiness are analyzed and evaluated. Based on these results, the applicability of SPR and adhesive bonding are proposed as an alternative to resistance spot welding.

• Journal of the Korean Ceramic Society
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• v.11 no.1
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• pp.23-28
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• 1974

1. Stage crushing by jaw crusher, steel mortar, and ball mill in turn has shown an inclination to increase the distribution of andalusite in coarse particles as well as to increase that of micas in fine particles. 2. Water elutriation was effective for the removal of muscovite and magnetic separation was effective for that of Mg-Fe micas such as biotte and chlorite. The process of concentration and that of purification are diagramatized respectively as follows: Concentration; Raw andalusite${\lightarrow}$Crushing${\lightarrow}$Screening${\lightarrow}$Water elutriation${\lightarrow}$Magnetic separation Purification; Concentrated andalusite${\lightarrow}$Calcination${\lightarrow}$Ball milling${\lightarrow}$Screening${\lightarrow}$Water elutriation${\lightarrow}$Magnetic separation${\lightarrow}$Acid washing.

• Proceedings of the KSME Conference
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• 2001.11a
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• pp.431-436
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• 2001

A finite analysis of tractor cabin for ROPS design was performed. Finite element model was made to take account of the tractor cabin structures. Four tests were defined in OECD standard; (1) longitudinal loading (2) rear crushing test (3) side loading (4) front crushing test. The results of four independent analyses and sequential analysis are compared with test results.

• Proceedings of the KSME Conference
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• 2003.04a
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• pp.19-24
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• 2003

Potential applications of foam-filled section are the automotive structures. A foam-filled section can be used for the front rail and firewall structures to absorb impact energy during frontal or side collision. In the case of side collision where bending is involved in the crushing mechanics, the foam filler will be significant in maintaining progressive crushing of the thin-walled structures so that more impact energy can be absorbed. In this study, the manufacturing process of closed cell aluminum alloy foam filled stainless steel tube was studied, and the various foam filled specimens including piecewise fillers were prepared, tested and discussed about the bending behaviors.