• Proceedings of the Korea Concrete Institute Conference
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• 2001.11a
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• pp.203-208
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• 2001

Objectives of this study included design of head and evaluation of the pullout performance of the headed reinforcement that can be used to replace standard hooks in the building exterior beam-column joints. Results of 36 pullout tests are presented. Test variables included reinforcing bar diameters (16-25mm), embedment depth (6-7db), transverse reinforcement, and single-vs.-group pullout behavior. The square head designed had gross area of 4Ab and thickness of db. The headed reinforcement made of Dl6 bars developed pullout strengths close to the bar yield strength, but larger bars developed strengths smaller than the yield strengths. The pullout resistance increased with decreasing spacing of the transverse reinforcement. Use of column ties with 6.0-db spacing improved the pullout performance of the headed bars without causing difficulties in fabricating the specimens. The comparison of the pullout performances between the headed bars and the standard hooks revealed that strengths, stiffnesses, and ductile behaviors are about the same.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.759-764
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• 2005

With the tunnel to case of the construction slope it executes the periodic maintenance due to an objectivity standard. But, the standard connected with construction slope is not integrated with the important public paper organic enemy and it is duplicated and the standards which conflict are being scattered. Also, it is referred to some specifications simply and the feature which is diffuse appears. Therefore, there is a necessity which it investigates the problem point of the maintenance civil official and it improves rationally and it takes a triangular position a confusedly be standard system. In this research which it sees accomplished the fundamental research against the inspection item classified by reinforcement method for the construction slope maintenance.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 1999.04a
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• pp.239-246
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• 1999

recently there have been many destructive seismic events in Kobe Japan in 1995 and in Northridge California USA in 1994. etc. The Korean Bridge Design Standard Specifications adopted the seismic design requirements in 1992. Comparing the earthquake magnitude in Korea with those in the west coast of the USA it may be said that the current seismic design requirements of the Korean Bridge Design Standard Specifications provides too conservation design results especially for transverse reinforcement details and amount in reinforced concrete columns. This fact usually makes construction problems in concrete casting due to transverse reinforcement congestion. And the effective stiffness Ieff depends on the axial load P(Ag{{{{ {f }_{ck } }}) and the longitudinal reinforcement ratio Ast/Ag and it is conservative to use the effective stiffness Ieff than the gross section moment Ig. Seismic design for transverse reinforcement content of concrete column is considered of extreme-fiber compression strain R-factor axial load and stiffness etc.

• Computers and Concrete
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• v.11 no.5
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• pp.463-473
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• 2013

As known, concrete classes are described as strength of standard specimens produced and kept in ideal conditions, not including reinforcement and not subjected to any load effect before. Under the circumstances, transforming core strengths to the standard specimen strength is necessary and considering all parameters, affected on the core strength, is inevitable. In fact, effects of the reinforcement and the load history on concrete strength are generally neglected when these mentioned transforms are performing. The main purpose of this paper is investigating the effects of the reinforcement and the load history on the core strength. This investigation is experimentally performed on cores drilled from specimens having different keeping conditions, reinforced, unreinforced, subjected to bending and central pressure in various proportions of failure load during specified periods. Obtained results show that the importance of these effects cannot be neglected.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.10a
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• pp.751-754
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• 1999

Corrosion inhibitors are widely used to protect chloride-induced corrosion of reinforcement in concrete. However, the number of researches on the corrosion of reinforcement, when corrosion inhibitor is used, is not enough for actual application in the field. In addition, on corrosion of reinforcement a quantitative standard about corrosion inhibitor does not exist and the data about its influencing concrete are relatively rare. In this study, the effectiveness of rebar corrosion protection, setting time, compressive strength, chloride ion's penetration, and diffusion test were performed using with three different kinds of corrosion inhibitors.

• Proceedings of the Korean Geotechical Society Conference
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• 2006.03a
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• pp.1181-1186
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• 2006

This study analyzed the reductive effect of lateral flow by the section and height of reinforcement of EPS. The conclusions of the study are as follows. (1) The lateral flow increased as the section of reinforcement decreased. The reinforcement section that satisfied the allowable range of the lateral flow turned out to beapproximately 80% of the standard reinforcement section. (2) As reinforcement height was decreasing, the lateral flow increased. The reinforcement heigh that satisfied the allowable range of the lateral flow turned out to be approximately 50% of the total lateral height of abutment.

• Journal of Ocean Engineering and Technology
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• v.15 no.1
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• pp.98-103
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• 2001

This paper is conducted to compare the seismic design standard of a bridge column such as the Korean Bridge Design Standard(KBDS), EC 8, NZS 3101 and ATC 32. The KBDS adopted the seismic design requirements in 1992. The earthquake magnitude in Korea is compared with those in the west coast of the USA. It may be said that the current seismic design requirements of the KBDS provides design results, that are too conservative especially for transverse reinforcement details and amounts in reinforced concrete columns. This fact usually creates construction problems in concrete casting, due to congestion of transverse reinforcement. Furthermore, the effective stiffness; $I_{eff}$ depends on both the axial load P/$A_gF_{ck}$ and the longitudinal reinforcement ratio $A_{st}/A_g, so it is the conservative to use the effective stiffness I$_{eff}$ than the gross section stiffness Ig. Seismic design for the transverse reinforcement content of the concrete column was analyzed and considered to have an extreme-fiber compression strain, response modification factor, axial load and effective stiffness etc.c.

• Architectural research
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• v.20 no.3
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• pp.83-92
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• 2018

Recently, there has been inter-Korean exchanges are active, in company with an assertive international activity with North Korea and inter-Korean Summits. Thus, there is a growing possibility of Korean reunification. However, when the unification situation occurs, population inflow by North Korean residents will be expected, and it will be necessary to prepare a housing supply strategy. In addition, even if North Koreans are prevented from entering, a plan is necessary to ensure structural safety since most buildings in North Korea are aging and a recent natural disaster occurs frequently. In this research, we will try to present a temporary housing supply strategy and a short-term structural reinforcement plan based on analysis of the standard housing conditions in North Korea. In this research, we represent the analysis result of the existing construction level, supply status and structural performance of North Korea. When we consider the reinforcement period and social costs, a short-term reinforcement plan is recommended rather than the full reinforcement of the aged housing in North Korea. Furthermore, we examine the ways to secure the residential safety of North Koreans through a case study of domestic and overseas temporary residential facilities, until the permanent residential facilities were supplied. According to the analysis, the tent houses were used as a form of relief housing in overseas frequently. However, the tent house is difficult to apply for domestic country with clear seasons due to insulation and heating problems. Therefore, it is appropriate to develop a residential supply strategy as focusing on the temporary housing facilities in assembled or container from, in preparation for the future population inflow.

• Journal of Korean Association for Spatial Structures
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• v.17 no.3
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• pp.83-90
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• 2017

Preservation of wooden structure due to deterioration and corrosion is based on preservation of original form, and wooden member should not be arbitrarily replaced or damaged. Accordingly, preservation processing method with synthetic resins is embossed. But it has an adverse effect because there is no exact standard for the reinforcement ratio with the synthetic. This paper experimental study for reinforcement ratio of wooden compressive member with synthetic resins, Reinforced ratio on section area of compressive member and direction. As a result, synthetic resin reinforcement selected as experimental variables by proper ratio enhanced compressive capacity of reinforced wooden member, than new wooden member.

• Proceedings of the Korea Concrete Institute Conference
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• 1996.04a
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• pp.289-294
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• 1996

This paper persents the assessment of the minimum shear reinforcement requirements in normal, medium and high-strength reinforced concrete beams. Twelve shear tests were conducted on full-scale beam specimens having design concrete compressive strengths of 35, 70 and 100 MPa. Different amounts of minimum shear reinfrocement were investigated, including the amounts required by Korean Concrete Standard (KCI88), JCI86, ACI89 (revised 1992) and CSA94 standard. The performance of the different amounts of shear reinforcement are discussed in terms of the shear capacity, the ductility and the crack control at service load levels. An assessment of code provisions for minimum shear reinforcememt, and the prediction and comparison of the ultimate shear capacity are also presented.