• Advances in concrete construction
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• v.10 no.1
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• pp.81-92
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• 2020

Flexural and splitting strength behavior of conventional concrete can significantly be improved by incorporating the fibers in it. A significant number of research studies have been conducted on various types of fibers and their influence on the tensile capacity of concrete. However, as an important property, tensile capacity of fiber reinforced concrete (FRC) is not modelled properly. Therefore, this paper intends to formulate a model based on experiments that show the relationship between the fiber properties such as the aspect ratio (length/diameter), fiber content, compressive strength, flexural strength and splitting strength of FRC. For the purpose of modeling, various FRC mixes only with steel fiber are adopted from the existing research papers. Automated neural network search (ANS) is then developed and used to investigate the effect of input parameters such as fiber content, aspect ratio and compressive strength to the output parameters of flexural and splitting strength of FRC. It is found that the ANS model can be used to predict the flexural and splitting strength of FRC in a sensible precision.

• Food Science of Animal Resources
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• v.37 no.6
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• pp.948-954
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• 2017

The objective of this study was to investigate the relationship between muscle fiber characteristics and fatty acid composition of four major muscles in Korean native black goat (KNBG). Longissimus lumborum (LL), psoas major (PM), semimembranosus (SM), and gluteus medius (GM) were obtained from five male KNBGs of 36 mon of age and subjected to histochemical analysis and to determine fatty acid composition and meat quality traits. There were significant (p<0.05) differences in fiber number percentage (FNP) and fiber area percentage (FAP) of fiber types among these four muscles. PM had the highest FNP of type I and the lowest FNP of type IIB, while SM had the highest FNP of type IIB. The highest fat content was observed in LL while SM had the lowest fat content. The proportions of SFA and MUFA were significantly (p<0.05) different among four muscles due to differences in the majority of fatty acids such as oleic (C18:1) and palmitic (C16:0) acids. The PUFA/SFA ratio was significantly (p<0.05) different among four muscles, and the highest PUFA/SFA ratio was observed in PM. Results suggested that LL and PM might be healthful because of higher desirable fatty acid value and PUFA/SFA ratio, respectively. Also, data showed that correlations between muscle fiber types and fatty acids proportion of goat muscles were reversed with those of cattle muscles.

• Journal of the Korean Geosynthetics Society
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• v.2 no.1
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• pp.27-37
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• 2003

The factors affecting shear strength and friction characteristics of the fiber-mixed soil can be classified into engineering properties of soil; particle-size, distribution, and particle shape, physical and mechanical properties of fiber; shape, length, diameter, tensile strength, elastic modulus, friction coefficient, and mixed ratio and external factors; confined stress and compaction condition. In this study, a series of shear friction tests and pull-out tests were performed to evaluate the friction properties of fiber-mixed soil according to soil type, fiber type, fiber mixed ratio and compaction degree. The materials and test conditions used in this study are as follows. Soils: SM and ML; mixing fibers: three types of polypropylene fibers(net type 38mm and 60mm, and line type 60mm); reinforcement: geogrid; mixing ratio: 0.2% and 0.3%; degree of compaction : 85% and 95%.

• Magazine of the Korea Concrete Institute
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• v.5 no.4
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• pp.156-166
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• 1993

The results of an experimental study on the manufacture and the mechanical properties of steel fiber reinforced polyester resin composites utilizing industrial waste products(fly ash) are presented in this paper. The composites using steel fiber, fly ash, unsaturated polyester resin, styrene monomer, catalyst (cobalt octate) and accelerator(methyl ethyl ketone peroxide), fine and coarse aggreates were prepared using various mixing conditions. As the test results show. the mechanical and physical properties, such as the compressive, tensile and flexural strengths, and the setting shrinkage of fly ash$\cdot$polyester resin composites were improved considerably by increasing the fly ash-binder ratio. And the workability of steel fiber reinforced fly ash$\cdot$polyester resin composites was reduced with increasing the fly ash-binder ratio and steel fiber content. Also, the compressive, flexural strength and toughness of the composites were remarkably increased by increasing steel fiber content.

• Journal of the Korean GEO-environmental Society
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• v.13 no.8
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• pp.45-55
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• 2012

This study is about the application of waste stone sludge as fill material. Waste stone sludge, weathered granite soil, and the mixture of the former and the latter strengthened with staple fiber are experimentally analyzed for measuring strength property. When staple fiber was mixed with waste stone sludge, weathered granite soil, and the mixture, there was a nearly linear relationship between the amount of the staple fiber and the increasing ratio of unconfined compressive strength. The increasing ratio of unconfined compressive strength was the largest in weathered granite soil. The increasing ratio of unconfined compressive strength of the mixture was similar to that of waste stone sludge. In the case of the mixture of weathered granite soil and waste stone sludge, an internal friction angle tended to increases rely on increasement of staple fiber content, whereas the change of cohesion was small. An internal friction angle was increased by 21 percent when staple fiber content is 0.75 percent. Comparing with weathered granite soil or waste stone sludge, strength parameters of the mixture were increased relatively. Thus strengthening effect of staple fiber in the mixture is expected.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.4
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• pp.647-653
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• 1994

This study was conducted to investigate the contents of dietary fiber (DF), compositions of fatty acids in lipid fraction and amino acids in salt-soluble protein from the functional food source such as Platycodi radix, perilla seed, evening primrose seed and aloe vera. The contents of dietary fiber, neutral detergent fiber (N.D.F) , acid detergent fiber( A.D.F) . kignin, hemicellulose an dcellulose in evening primorse seed were higher than those of other samples, except the content of cellulose .The ration of polyunsaturated /saturated (P/S) fatty acid in total lipids was 6.31 in perilla seed, which was higher than those of other samples. The content of linolenic acid (n-3) in perilla seed was 55.47%. The content of linoleic acid (n-6) in evening primrose seed was 71.88% , which was higher than those of other samples. The fatty acid composition in neutral lipids were the same as those of total lipids. The PUFA contents of fatty acid in glycolipids were 61.76% in perilla seed. And also, the ratio of n-6/n-3 in evening primrose seed was 15.19. The fatty acid compositions in phospholipids were the sameas those of glycolipids. The contents of PUFA in Platycodi radix were 62.96% . The essential amino acid contents of salt-soluble protein were 47 mole % in Platycodi radix , which was slightly higher than those other samples. The ration of essential amino acid /nonessential amino acid (E/N) was 0.9 and 0.66 in Platycodi radix and aloe vera, respectively.

• Journal of the Korea Concrete Institute
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• v.28 no.1
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• pp.95-104
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• 2016

Flexural strength of concrete ground slab reinforced with steel fiber is evaluated using the equivalent flexural strength ratio of steel fiber reinforced concrete based on the yield line theory. Recently, the European standard specifies that the tensile performance of the steel fiber reinforced concrete be evaluated directly from the residual flexural strength after the cracking of concrete. Thus, in the study, an experiment was carried out to evaluate the conventional equivalent flexural strength ratio and the residual flexural strength of the steel fiber reinforced concrete. Then the design flexural strength was investigated according to the location of a point load, based on the ratio of the radius of contact area of the load to the radius of relative stiffness. Design flexural capacity obtained from ACI 360R-10 was smaller than that from TR 34 (2003 & 2013). In addition, TR 34 (2013), which evaluates the design flexural capacity based on the residual flexural strength, showed slightly smaller value than TR 34 (2003).

• Composites Research
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• v.20 no.6
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• pp.1-7
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• 2007

Expanded graphite/carbon fiber hybrid conductive polymer composites were fabricated by the preform molding technique. The conductive fillers were mechanically mixed with a phenol resin to provide an electrical property to composites. The conductive filler loading was fixed at 60wt.% to accomplish a high electrical conductivity. Expanded graphites were excellent in forming a conductive networking by direct contacts between them while it was hard to get the high flexural strength over 40MPa with using only expanded graphite and phenol resin. In this study, carbon fibers were added in composites to compensate the weakened flexural strength. The effect of carbon fibers on the mechanical and electrical properties was examined according to the weight ratio of carbon fiber. As the carbon fiber ratio increased, the flexural strength increased until the carbon fiber ratio of 24wt.%, and then decreased afterward. The electrical conductivity gradually decreased as the increase of the carbon fiber ratio. This was attributed to the non-conducting regions generated among the carbon fibers and the reduction of the direct contact areas between expanded graphites.

• Proceedings of the Korean Fiber Society Conference
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• 1995.04a
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• pp.33-34
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• 1995

• Korean Journal of Plant Resources
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• v.11 no.3
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• pp.358-362
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• 1998

This study was carried out to examine the effect on the contents of dietary fiber, mechanical properties, and sensory quality of bread contained with 10% of high-fiber Camellia (Camellia japonica L.) seed flour. Bread added by dietary fiber was the contents of moisture, protein and ash higher than control bread, while the contents of lipid lower than that of control bread. The high-fiber with Camellia seed flour contained 8.6% soluble dietary fiber, 43.7% insoluble dietary fiber, and 52.3% total dietary fiber. The ratio of insoluble dietary fiber/soluble dietary fiber in the high-fiber with Camelia seed flour was 5 times. Bread with the addition of dietary fiber contained 6.9% total dietary fiber. With the addition of dietary fiber, water absorption , mixing time loaf weight, and hardness increased, but the loaf volume decreased . The sensory quality on bread added by dietary fiber was somewhat low in color, appearance, crumb texture, mouthfeel, flavor and overall preference was higher than that of control bread.