• Journal of Korean Association for Spatial Structures
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• v.7 no.1 s.23
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• pp.79-85
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• 2007

Steel plate bonding method with epoxy is common applied to repair and strengthen RC structures, but Steel is apt to corrode quickly, hard to manufacture and heavy. To overcome these defects, it is carried out research on strengthening RC structures with FRP(Fibre Reinforced Polyrner/Plastic) FRP is generally used in the shape of Plate or Sheet, but it has weak point such as premature failure, difficult work. To cope with these problem, NSMR(Near Surface Mounted Reinforcement) which uses CFRP in the shape of Rod is proposed and carried out active research on strengthening effect of variables such as quantity, anchorage length and space of CFRP-Rod. Strengthening with CFRP-Rod is carried out under loading to some degree in fact, and so the amount of pre-loading is selected as variable in this research. The amount of pre-loading is chosen in proportion to nominal strength of non-strengthened specimen with CFRP-Rod.

• Proceedings of the Korea Water Resources Association Conference
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• 2010.05a
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• pp.1089-1093
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• 2010

최근 하천의 자연성 및 생태기능의 향상을 위해 매트류 호안공법의 적용이 증가하고 있다. 이러한 공법이 적용된 호안은 강수 및 하천수의 지속적인 유입으로 인해 앵커핀과 비탈면 간의 마찰력을 저하시킬 수 있다. 마찰력의 저하는 앵커핀의 고정능력을 저하시켜 매트가 들뜨는 현상을 발생시키고, 이로 말미암아 비탈면에 식재된 식생의 고사는 물론 비탈면의 슬라이딩 현상의 발생에 의해 비탈면 붕괴에 까지 이르게 하고 있다. 그러나 현재 호안매트와 함게 시공하는 앵커핀의 적용에 대한 구체적인 기준과 연구가 미흡한 실정이다. 본 연구에서는 매트류 호안제품을 비탈면에 고정시키는 목적으로 사용하고 있는 앵커핀에 대한 인발특성을 파악하고자 하였다. 인발실험에 사용된 앵커핀은 실제 하천호안에 적용되고 있는 상용제품으로 형태가 다른 4가지 type을 실험에 사용하였으며, 앵커핀의 관입깊이(170mm, 250mm) 별로 인발실험을 실시하였다. 실험에 사용된 인발장치는 인발부에 로드셀을 장착하여 앵커핀과 결합이 가능하도록 하였으며, 인발시 발생하는 계측 값을 컴퓨터를 통해 출력이 가능하도록 제작하였다. 실험결과 4가지 형태의 앵커핀에 대한 관입깊이별 형태별 인발특성을 파악할 수 있었으며, 비탈면 및 매트의 고정효과가 우수한 앵커핀의 형태에 대해서도 파악할 수 있었다. 관입깊이별 최대 인발력은 두 변위(170mm, 250mm) 모두 Type 4가 337N, 594N 으로 가장 큰 인발력을 가지는 것으로 측정되었으며, 변위에 의한 인발력의 증가는 Type 2가 138%로 가장 큰 폭의 증가 값을 보였다. 또한 토양과 앵커핀의 마찰력 향상을 위해 하부가 돌출된 형태로 제작된 Type 2와 Type 4가 상대적으로 실험 후반부에서 최대 인발력이 발생하고 인발지속시간이 길게 나타나는 것으로 볼 때, 인발저항은 앵커핀 하부의 돌출면적에 영향을 받는 것으로 판단된다.

• Land and Housing Review
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• v.6 no.1
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• pp.11-19
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• 2015

This paper presents experimental results on detailing of boundary element transverse reinforcement, proposed to alleviate placement detailing of special shear wall experiencing difficulty in construction at the sites due to recently reinforced seismic regulations, according to the type and placement interval of transverse reinforcement. As a result of experiment, crack and destruction aspects of SSWR series specimen that employed the proposed detailing of transverse reinforcement showed similar trend as SSW series specimen that used closed hoop. Predicted maximum strength values were exceeded. Also as a result of comparing energy dissipation ability, SSWR2 specimen that follows alleviated placement detailing was found to have similar seismic performance as special shear wall SSW2 specimen based on the existing design standard. As it satisfies the deformation angle condition of 1.5% provided in the design standard, SSWR2 can be used as the main lateral force resistance element in structures.

• Korean Journal of Construction Engineering and Management
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• v.15 no.3
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• pp.66-73
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• 2014

The Korean construction industry has been severely impacted by the 2008 global financial crisis, which resulted in a significant reduction in the overall contract amount. For survival, many construction management (CM) companies had to adapt a strategy of lowering bid prices to maintain their competitiveness. As a result of the strategy, companies faced a number of issues including their decreased capability in risk management. However, most risk management-related studies focused on construction risk management, yet these studies lacked consideration of enterprise-level risk management practices. To fill the gap, the objectives of the present study are (1) to investigate, the risk management practices of Korean CM companies, (2) to identify factors that determine efficient enterprise-level risk management practices, and (3) to propose a module for the development of enterprise-level risk management. Lastly, the efficiency of the proposed development module was validated by using a survey.

• Journal of the Korean GEO-environmental Society
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• v.6 no.2
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• pp.31-38
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• 2005

Flowable fills are self-leveling, liquid-like materials, and self-compacting to 95-100% of the maximum unit weight. Benefits of flowable fills include limited required labor, accelerated construction, ready placement at inaccessible locations, and the ability to be manually re-excavated. Applications for flowable fills include utility trenches, building excavations, underground storage tanks, abandoned sewers and utility lines, and filling underground mine shafts The objective of this study is to estimate engineering property of flowable fills made of soil mixed with recycled stylofoam and stabilizer for using geotechnical field. For this study, the uniaxial compression test, flowable test, and model tests were performed. Based on the results of the tests, the following conclusions are : fills made of soil mixed with recycled stylofoam and stabilizer can be used as flowable fills, minimum stabilizer quantity for using flowable fills ranges from 1.0($kN/m^3$) to 1.2 ($kN/m^3$).

• Journal of the Korea institute for structural maintenance and inspection
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• v.10 no.6
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• pp.87-94
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• 2006

Estimating moving vehicle loads is important in modeling design loads for bridge design and construction. The paper proposes a moving force identification algorithm using moment influence lines measured at multi-axes. Density estimation function was applied to estimate more than two wheel loads when estimated load values fluctuated severely. The algorithm has been examined through simulation studies on a simple-span plate-girder bridge. Influences of measurement noise and error in velocity on the identification results were investigated in the simulation study. Also, laboratory experiments were carried out to examine the algorithm. The load identification capability was dependent on the type and speed of moving loads, but the developed algorithm could identify loads within 10% error in maximum.

• Journal of the Korea institute for structural maintenance and inspection
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• v.21 no.3
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• pp.86-92
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• 2017

The possibility to development of floor vibration problem is larger in case of long span structure under service loads. Therefore, to improve the vibration performance of the floor, increasing of its thickness is a common method. But, increasing of thickness can lead to increase of slab self weight and reduce the effectiveness of the building. For this reason, attention for voided slab which reduces the self-weight is increasing. Hence, voided deck slab combined with deck plate and polystyrene void foam which has buoyancy prevention capacity and much developed construct ability has bee developed. By using the developed voided slab, vibration performance of a mock-up building structure has been investigated in the current study. The results according to analysis showed that they can be implemented in living and bedroom which are considered as 1st grade on the basis of "Residential Evaluation Guidelines for Vibration of Buildings" by the Architectural Institute of Japan.

• Journal of Korean Society of Steel Construction
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• v.18 no.2
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• pp.147-160
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• 2006

GA-based fuzzy optimum design algorithm incorporated with the refined plastic hinge analysis method is presented in this study. In the refined plastic hinge analysis method, geometric nonlinearity is considered by using the stability functions of the beam-column members. Material nonlinearity is also considered by using the gradual stiffness degradation model, which considers the effects of residual stresses, moment redistribution through the occurence of plastic hinges, and the geometric imperfections of the members. In the genetic algorithm, the tournament selection method and the total weight of the steel frames. The requirements of load-carrying capacity, serviceability, ductility, and constructabil ity are used as the constraint conditions. In fuzzy optimization, for crisp objective function and fuzzy constraint s, the tolerance that is accepted is 5% of the constraints. Furthermore, a level-cut method is presented from 0 to 1 at a 0 .2 interval, with the use of the nonmembership function, to solve fuzzy-optimization problems. The values of conventional GA optimization and fuzzy GA optimization are compared in several examples of steel structures.

• Journal of Korea Water Resources Association
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• v.40 no.2 s.175
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• pp.125-134
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• 2007

The objective of this study was to investigate the applicability of new vegetation revetment techniques. The applicability of revetments was confirmed with respect to flood safety as well as environmental consideration. The safety against flood was examined through an in situ experiment at Dong-moon Stream located in Paju and a laboratory experiment. The environment-friendly characteristics of revetments were analyzed by using the results of a 2-year in situ monitoring. It was found that the revetments investigated in this study had a safety capability against floods and high vegetating capability. Application ranges of design factors were suggested for each revetment developed in this study.

• The Journal of the Korea Contents Association
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• v.19 no.4
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• pp.546-555
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• 2019

This study aims to suggest a development process for the interior design major course at K University's school of design to educate specialists who can answer the needs of the industrial field. The study procedure first analyzed the internal and external environment to establish queries and development direction. A job model for the interior design industry was constructed while course modules were deducted based on job characteristics and was used to form a curriculum based on a 4 year course. Required personnel includes 'Interior Design Business and Marketing Specialists', 'Interior Design Space Planning Specialists' and 'Interior Design Construction Management Specialists'. 40 modules were drawn following the detailed job model structure. 1st year students are to follow a common curriculum, 2nd years the major foundation, 3rd years major intensive, and the 4th years major application. The practical importance of the research is to suggest a development process of major modules based on the standard job model and the organization structure of the interior design industry.