• Steel and Composite Structures
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• v.26 no.6
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• pp.793-808
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• 2018

In this study, the seismic performance of the connections between L-shaped columns composed of concrete-filled steel tubes (L-CFST columns) and H-beams used in high-rise steel frame structures was investigated. Seven full-scale specimens were tested under quasi-static cyclic loading. The variables studied in the tests included the joint type, the axial compression ratio, the presence of concrete, the width-to-thickness ratio and the internal extension length of the side plates. The hysteretic response, strength degradation, stiffness degradation, ductility, plastic rotation capacity, energy dissipation capacity and the strain distribution were evaluated at different load cycles. The test results indicated that both the corner and exterior joint specimens failed due to local buckling and crack within the beam flange adjacent to the end of the side plates. However, the failure modes of the interior joint specimens primarily included local buckling and crack at the end plates and curved corners of the beam flange. A design method was proposed for the flexural capacity of the end plate connection in the interior joint. Good agreement was observed between the theoretical and test results of both the yield and ultimate flexural capacity of the end plate connection.

• Explosives and Blasting
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• v.29 no.2
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• pp.1-12
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• 2011

Progressive collapse analyses of high-rise buildings subjected to abnormal loading such as fires, impacts, earthquakes, typhoon, bomb blasts etc. are intended. However it is difficult to perform collapse experiments of the real scale building to determine the capacity of the structure under an extreme loading events. In this study, collapse behavior of a 15 story RC structure building loaded by external explosion pressures were simulated using Extreme Loading Structures (ELS) software. The standoff distance between the RC building and explosives of 1500 kg was 1, 2, 5, 10, and 15 meters. The explosive demolition analysis techniques based on removal of partial support structures following blast scenario was adapted to investigate the transition process of progressive collapse-local damage.

• Journal of the Earthquake Engineering Society of Korea
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• v.8 no.1
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• pp.39-58
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• 2004

It is very important that predict the inelastic seismic behavior exactly for seismic performance evaluation of a building in the performance based seismic design. Evaluation method of seismic performance based on the pushover analysis reflected in PBSE was developed by some researchers. For the evaluation of inelastic global and local seismic responses by pushover analysis exactly. lateral load distribution should be adjusted and reflected the dynamic characteristics of structural system and various seismic ground motions. And performance point should be determined based on the evaluation of reasonable deformation capacity of a building more exactly. An effective method based on the improved the adaptive lateral load distribution and the equivalent responses of a multistory building is proposed in this study to efficiently estimate the accurate inelastic seismic responses. The proposed method can be used to evaluate the seismic performance for the global inelastic behavior of a building and to accurately estimate its local inelastic seismic responses. In order to demonstrate the accuracy and validity of this method, inelastic seismic responses estimated by the proposed method are compared with those obtained from other analytical methods.

• Asian Journal for Public Opinion Research
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• v.3 no.1
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• pp.1-21
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• 2015

A recent public opinion survey found that the anti-corporate sentiment of South Korean citizens is primarily due to the misbehavior of Korean corporations. South Korean citizens' skepticism of corporations may hinder the democratic and economic development of the country. As a driving force for community development, social capital is considered to enable citizens to collaborate with one another to resolve a shared problem. Specifically, this study pays attention to the relationship among social capital, corporate capacity, and trust, which may perhaps contribute to developing a democratic environment in Korean society. The study aims to explore whether Korean citizens' perceived corporate bonding and bridging social capital affect corporate capacity for collaborative action and trust in corporations. A Web survey of 385 South Koreans was conducted. The findings show that perceived bonding social capital among employees is positively related to corporate capacity for collaboration action. Moreover, perceived bonding among employees and bridging social capital between employees and local residents are positively related to corporate capacity for collaboration action and trust in corporations. These findings suggest that researchers and practitioners for organizational development and community-building need to enhance corporate social capital.

• Earthquakes and Structures
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• v.9 no.2
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• pp.375-390
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• 2015

Staircase is a vertical transportation element commonly used in every multistoried structure. Inclined flights of staircase are usually casted monolithically with RC frame. The structural configuration of stairs generally introduces discontinuities into the typical regular reinforced concrete frame composed of beams and columns. Inclined position of flight transfers both vertical as well as horizontal forces in the frame. Under lateral loading, staircase in a multistory RC frame building develops truss action creating a local stiffening effect. In case of seismic event the stiff area around staircase attracts larger force. Therefore, special attention is required while modeling and analyzing the building with staircase. However, in general design practice, designers usually ignore the staircase while modeling either due to ignorance or to avoid complexity. A numerical study has been conducted to examine the effect of ignoring staircase in modeling and design of RC frame buildings while they are really present in structure, may be at different locations. Linear dynamic analysis is performed on nine separate building models to evaluate influence of staircase on dynamic characteristics of building, followed by nonlinear static analysis on the same models to access their seismic performance. It is observed that effect of ignoring staircase in modeling is severe and leads to unsafe structure. Effect of location and orientation of staircase is also important in determining seismic performance of RC frame buildings.

• Journal of the Earthquake Engineering Society of Korea
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• v.22 no.3
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• pp.185-191
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• 2018

Post-earthquake risk assessment technique in Korea is developed in 2013 by National Disaster Management Research Institute, at the same time, related manual and standard regulation is distributed to every local government by National Emergency Management Agency. The objectives of this research are to investigate and evaluate the post-earthquake risk assessment of 9.12 Earthquake (M5.8, Gyeongju City, 2016) and 11.15 Earthquake (M5.4, Pohang City, 2017). To suggest and improve the assessment process of post-earthquake risk, first post-earthquake risk assessment method of advanced foreign countries including US, New Zealand and Japan are compared, and post-earthquake evaluation activities in 9.12 Earthquake and 11.15 Earthquake are analyzed. From the results, it is needed to expand the adapted building and structure types and strengthen the earthquake disaster response capacity of local government.

• Structural Engineering and Mechanics
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• v.80 no.6
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• pp.737-747
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• 2021

The objective of seismic resilience is to maintain or rapidly restore the function of a building after an earthquake. An efficient tilt mechanism at the member level is crucial for the restoration of the main structure function; however, the damage resistance of the members should be the main focus. In this study, through a comparison with the classical Flamant theory of local loading in the elastic half-space, an elastomechanical solution for the axial-stress distribution of a reinforced-concrete (RC) rocking column was derived. Furthermore, assuming that the lateral displacement of the rocking column is determined by the contact surface rotation angle of the column end and bending and shear deformation of the column body, the load-lateral displacement mechanical model of the RC rocking column was established and validated through a comparison with finite-element simulation results. The axial-compression ratio and column-end strength were analyzed, and the results indicated that on the premise of column damage resistance, simply increasing the axial-compression ratio increases the lateral loading capacity of the column but is ineffective for improving the lateral-displacement capacity. The lateral loading and displacement of the column are significantly improved as the strength of the column end material increases. Therefore, it is feasible to improve the working performance of RC rocking columns via local reinforcement of the column end.

• Steel and Composite Structures
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• v.41 no.6
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• pp.861-871
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• 2021

This study aims at investigating the hysteretic performance of a novel composite wall panel fabricated by infilling aerated concrete blocks into a novel light-steel frame used for low-rise residential buildings. The novel light-steel frame is consisted of two thin-wall rectangular hollow section columns and a truss-beam assembled using patented U-shape connectors. Two bare light-steel frames and two composite wall panels have been tested to failure under horizontal cyclic loading. Hysteretic curves, lateral resistance and stiffness of four specimens have been investigated and analyzed. Based on the testing results, it is found that the masonry infill can significantly increase the lateral resistance and stiffness of the novel light-steel frame, about 2.3~3 and 21.2~31.5 times, respectively. Failure mode of the light-steel frame is local yielding of the column. For the composite wall panel, firstly, masonry infill is crushed, subsequently, local yielding may occur at the column if loading continues. Hysteretic curve of the composite wall panel obtained is not plump, implying a poor energy dissipation capacity. However, the light-steel frame of the composite wall panel can dissipate more energy after the masonry infill is crushed. Therefore, the composite wall panel has a much higher energy dissipation capacity compared to the bare light-steel frame.

• The Journal of Fisheries Business Administration
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• v.40 no.3
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• pp.1-28
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• 2009

In recent, the Korean fisheries industry face an overall crisis. Annual fish catch is continuously decreasing for last two decades even though various programs to improve fish population. Moreover, domestic fish market is more and more occupied by imported cheap fish products from abroad due to the consequence of open economic policy, FTA and WTO/DDA entente. Under the circumstances, this study aims to examine the potential for building fisheries cluster as a policy tool to promote fisheries and fisheries-associated industries in Korea. To achieve this goal, the authors firstly reviewed the theoretical concept of Industrial Cluster in the evolutionary economics point of view, secondly, analyzed the main components of Porterian Cluster(or innovation cluster), thirdly, derived the key reasons to induce the improvement of productivity within the cluster network system and lastly evaluated fisheries capability and industrial infrastructures of each province as a basic condition to build a fisheries cluster. The result of the study demonstrates the voluntary accumulation of fish products and processing techniques in Korea, however, it is not enough to make up a Porterian innovation. Therefore, the present is most opportune for applying fisheries cluster as a strategic policy tool. Government supports to establish innovation cluster for fisheries may contribute both fisheries industry and local economy by developing the latent capacity of fisheries and helping concentrate innovation capabilities.

• Korean Journal of Health Education and Promotion
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• v.26 no.3
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• pp.35-48
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• 2009

Objectives: The community network is a foundation laid by the local community which has been formed historically and geographically to develop itself. This paper as a Korean way of healthy network survey for the community capacity building is an exploratory research to grasp the character of Korean society and then to organize an resident-governing partnership for that. Methods: Research objectives are CBOs(Community-Based Organizations) in S-district of Seoul. This region is a new town, however the solidarity and volunteerism of this resident is lively. The survey tool is Cho's CBOs Evaluation Questionnaire which was originated to measure the community capacity. The period of survey is from the January 2009 to the March 2009 and the study organizations which were collected by snowball sampling were 80. Results: The result shows two main networks: one is the civil society and craft union cluster, the other is welfare organization cluster. Groups of high centrality were organizations whose members are mainly women and craft organizations which were organized before 1990's. The group of high betweenness was the Association of Women's Organizations(0.188). Bi-components were six and they could be divided by organization's aim. In terms of the determinants of the participation to the health center enterprise, only the number of link(B=-0.60, p<0.04) was statistically significant. It means that when organization variables are controlled a tendency appears: the more the voluntary associations network, the less participation in the health enterprise. Conclusion: CBHOs(Community-Based Health Organizations) enhances residents' spontaneity and cohesion to increase the capability of the local community. If the surveyed healthy network, together the community health project, are used for various community development projects, the existing CBOs including CBHOs will be reorganized and furthered newly. For this it will be needed to construct an effective partnership of healthy network by restructuring the existing networks of voluntary associations.