• Structural Engineering and Mechanics
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• v.30 no.6
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• pp.733-761
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• 2008

The failure of reinforced concrete structures in recent earthquakes caused concern about the performance of beam column joints. Confinement of joint is one of the ways to improve the performance of beam column joints during earthquakes. This paper describes an experimental study of exterior beam-column joints with two non-conventional reinforcement arrangements. One exterior beam-column joint of a six story building in seismic zone III of India was designed for earthquake loading. The transverse reinforcement of the joint assemblages were detailed as per IS 13920:1993 and IS 456:2000 respectively. The proposed nonconventional reinforcement was provided in the form of diagonal reinforcement on the faces of the joint, as a replacement of stirrups in the joint region for joints detailed as per IS 13920 and as additional reinforcement for joints detailed as per IS 456. These newly proposed detailing have the basic advantage of reducing the reinforcement congestion at the joint region. In order to study and compare the performance of joint with different detailing, four types of one-third scale specimens were cast (two numbers in each type). The main objective of the present study is to investigate the effectiveness of the proposed reinforcement detailing. All the specimens were tested under reverse cyclic loading, with appropriate axial load. From the test results, it was found that the beam-column joint having confining reinforcement as per IS: 456 with nonconventional detailing performed well. Test results indicate that the non-conventionally detailed specimens, Type 2 and Type 4 have an improvement in average ductility of 16% and 119% than their conventionally detailed counter parts (Type1 and Type 3). Further, the joint shear capacity of the Type 2 and Type 4 specimens are improved by 8.4% and 15.6% than the corresponding specimens of Type 1 and Type 3 respectively. The present study proposes a closed form expression to compute the yield and ultimate load of the system. This is accomplished using the theory of statics and the failure pattern observed during testing. Good correlation is found between the theoretical and experimental results.

• Journal of the Korea institute for structural maintenance and inspection
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• v.16 no.6
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• pp.1-8
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• 2012

This study estimates the performance of confined concrete according to the configuration of transverse steel bars. The main test variables were the yield strength of spiral reinforcement and configuration of transverse reinforcement. A total of 27 specimens with rectangular cross section were cast and tested under monotonic concentric compression. R-type specimens with rectangular spirals, C-type specimens with circular spirals and O-type specimens with combined shape of rectangular and octagon were designed in this study. From experimental results, it is concluded that the proposed configuration of transverse reinforcement can provided improved ductility to the confined concrete compared to rectangular spiral reinforcement.

• Journal of the Korean GEO-environmental Society
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• v.20 no.8
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• pp.13-20
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• 2019

In order to ground reinforcement, the chemical grouting, the anchor, the soil nailing system, the micropile, etc. can be mentioned by the methods widely used in domestic. The above ground reinforcement methods are developed by various methods depending on the type of reinforcement, installation method, presence of prestress, grouting method, etc. However, in common, the strength of reinforcement, the friction force of grout and reinforcement and the friction force of grout and ground are the main design variables. Therefore, the optimized ground reinforcement is a material with a high tensile strength of the reinforcement itself, the friction force between the reinforcement and the grout is high, and the application of an optimal grouting method is necessary to improve the friction force between the grout and the ground. In this study, a total of 20 model tests were conducted to analyze the reinforcement effects according to the shape of the reinforcement and the grouting method. As a result of the test, As a result of the experiment, it is judged that the reinforcing effect is superior to the perforated + wing type reinforcement and post grouting method.

• The Research Journal of the Costume Culture
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• v.19 no.3
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• pp.473-487
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• 2011

The purpose of this study is to analyze the body type and fashion of posthuman in SF movies. The method of this study was to analyze documentaries, internet web site, fashion books and so forth. The results were as follows: The body types of posthuman were expressed as mutation type, prosthetic type, clone type by biological hybrid or renovation and digital type by computer simulation. The mutation type was expressed as reinforcement of masculinity or feminity and reinforcement of body functions. The fashion item was expressed as a black tailored suit, leather jacket, cat suit, whip, black sunglass, garter belt, high heel shoes, short pants, black one piece dress and functional body suit. The prosthetic type was expressed as reinforcement of body functions and reinforcement of masculinity or feminity. The fashion item was expressed as a military item, high-tech power suit and ergonomic armor suit. The clone type was expressed as the plural ego with reinforcement of body functions. The fashion item was expressed as a power shoulder jacket, fake fur coat, vinyl, black see-through look and functional suit. The digital type was expressed as reinforcement of masculinity or feminity and the plural ego with reinforcement of body functions. The fashion item was expressed as a data suit, leather jacket, black over coat, boots, black sun glass, ethnic items and military items. The meanings of posthuman fashion in SF movies were impurity of posthuman, display of superhuman's power by sexuality, metaphor of power and fantasy of superhero in opposition futuristic dystopia. As mentioned above, posthuman body type and fashion in SF movies become the conversational topic in the real world. The fact that we think about utopia and identity of posthuman in the future is of great significance.

• Journal of Technologic Dentistry
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• v.42 no.2
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• pp.91-98
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• 2020

Purpose: This study is to compare the flexural strength and modulus by inserting a mesh and stick type fiberglass reinforcement into resin specimens. Methods: Wax specimens (length 64 mm, width 39 mm, thickness 5 mm) are prepared according to ISO 20795-1:2013. Mesh type and stick type glass fiber reinforcements were prepared. The prepared wax specimens were used plaster and flask for investment. The flask was separated and the wax was removed. The heat curing resin was injected into the flask, and then a mesh type and stick type fiberglass reinforcement were inserted. The prepared resin specimen was cut into three equal parts (length 64 mm, width 10 mm, thickness 3.3 mm). The mesh type glass fiber reinforcement (MT group) and the stick type glass fiber reinforcement (ST group) were classified into two groups. The prepared specimen was measured using a universal testing machine (UTM). The data were analyzed by Mann-Whitney U test, and the significance level was set to 0.05. Results: In the flexural strength, the ST group was higher than the MT group, and there was a significant difference between the two groups (p<0.05). In the flexural modulus, the ST group was higher than the MT group, and there was a significant difference between the two groups (p<0.05). Conclusion: The stick-type glass fiber inreased the flexural strength than the mesh-type glass fiber reinforcement.

• Advances in concrete construction
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• v.14 no.2
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• pp.79-92
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• 2022

The amount and configuration of transverse reinforcement are known as critical parameters that significantly affect the lateral confinement of concrete, the ductility capacity, and the plastic hinge length of RC columns. Based on test results, this study investigated the effect of the three variables on structural indexes such as neutral axis depth, lateral expansion of concrete, and ductility capacity. Five reinforced concrete column specimens were tested under cyclic flexure and shear while simultaneously subjected to a constant axial load. The columns were reinforced by two types of reinforcing steel: rectangular hoops and spiral type reinforcing bars. The variables in the test program were the shape, diameter, and yield strength of transverse reinforcement. The interactive influence of the amount of transverse reinforcement on the structural indexes was evaluated. Test results showed that when amounts of transverse reinforcement were similar, and yield strength of transverse reinforcement was 600 MPa or less, the neutral axis depth of a column with spiral type reinforcing bars was reduced by 28% compared with that of a column reinforced by existing rectangular hoops at peak strength. While the diagonal elements of spiral-type reinforcing bars significantly contributed to the lateral confinement of concrete, the strain of diagonal elements decreased with increases of their yield strength. It was confirmed that shapes of transverse reinforcement significantly affected the lateral confinement of concrete adjacent to plastic hinges. Transverse reinforcement with a yield strength exceeding 600 MPa, however, increased the neutral axis depth of normal-strength concrete columns at peak strength, resulting in reductions in ductility and energy dissipation capacity.

• KCI Concrete Journal
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• v.11 no.3
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• pp.201-210
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• 1999

An experimental study was carried out to determine pullout behavior of a new type of anchor bolt that used deformed reinforcement and a commercial adhesive. Concrete slabs and columns with about 20-MPa compressive strength were used for 136 pullout tests performed. Test variables included anchor diameter (10 mm ~ 32 mm). embedment depth (10$\Phi$ or 15$\Phi$), edge effect. and Presence of transverse reinforcement in existing concrete. In Tyre-S test. where the edge or reinforcing steel effect was not included, the anchor Pullout strengths increased with increasing anchor diameters. Anchors with 15$\Phi$ embedment depth had higher Pullout strengths than those with 100 embedment depth The largest average Pullout load of 208 kN was determined for anchors made with D25 reinforcement and with 15$\Phi$ embedment depth. In Type-E tests, where the anchors were installed close to the edge of existing concrete, there were reductions in pullout strengths when compared to those determined in Type-S tests. In Type-ER tests, influence of the reinforcement in existing concrete on the anchor pullout strengths was examined using reinforced concrete and plain concrete columns Test results indicated that existing transverse reinforcement (column ties) did not help increase the pullout strength. The overall pullout test results revealed that the new anchor bolt can develop large pullout strengths while the anchors can be made of materials that are readily available in the market.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.09a
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• pp.350-358
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• 2009

To enhance the application of the reinforced retaining walls in the railway industry, this paper suggested a type of reinforcement subgrade with short reinforcement and rigid facing. To become popular the reinforced retaining walls in the industry, the deformation of retaining walls should be controlled below some limited level. In this paper, small scale and full scale tests of the proposed retaining walls were performed and their deformation characteristics were evaluated. Even though it has short reinforcement, the rigid type retaining wall had small deformation to the external train loading than the segmental type retaining wall had.

• Journal of Korean Tunnelling and Underground Space Association
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• v.20 no.3
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• pp.625-639
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• 2018

This study is about the reinforcing type of reinforcement method which is reinforced in tunnel portal of tunnel with bad ground condition. Generally, it is known that the horizontal reinforcement method is more effective than the conventional reinforcement method. However, as a limitation of the tunnel construction technology, it is being constructed by the superposition reinforcement method. In recent years, high-strength large-diameter steel pipes and horizontally oriented longitudes (L = 30.0~50.0 m) construction technology have been developed. Therefore, it is required to study reinforcement method of tunnel portal reinforcement method. Therefore, 3-D numerical analysis (Midas GTS NX 3D) was performed by setting the reinforcement method (No reinforcement type, overlap reinforcement type and horizontal reinforcement type) and ground condition as parameters. As a result, it was considered that the reinforcement effect was the largest as the horizontal reinforcement type of the reinforcement method was the smallest in the displacement and the support material stress. Based on the results of the numerical analysis, horizontal steel pipe grouting was applied to the actual tunnel site. The displacement of the tunnel portal and the stress of the support material occurred within the allowable values and were considered to ensure sufficient stability.

• Land and Housing Review
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• v.4 no.4
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• pp.371-382
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• 2013

This study performs an experimental investigation to evaluate the behavior of RC flat plate interior joints specimens. Three 60 percent scale Flat Plate interior specimens assemblies representing a portion of a Flat Plate Apartment Structural System subjected to simulated seismic loading (unbalanced moments) under constant axial load were tested, including one specimens with ordinary shear reinforcement and two specimens with folded bend type shear reinforcement. Test results are shown that (1) the design code KBC 2009 is accurate estimate the behavior of specimens. (2) Two types shear reinforcement have a similar structural behavior, but construction work of rebar with folded bend type shear reinforcement is easier than that of ordinary shear reinforcement. (3) In moderate seismic region, RC Flat Plate interior joint with folded bend type shear reinforcement is apply to structural design of Flat Plate.