• Proceedings of the Computational Structural Engineering Institute Conference
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• 2010.04a
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• pp.150-153
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• 2010

본 논문에서는 비내진 설계된 철근콘크리트 골조로 이루어진 저층의 노후공동주택의 내진성능을 향상시키기 위한 구조물의 보강방법에 대해 연구하였다. 이를 위하여 비선형 정적 해석과 시간 이력 해석을 수행하여 추가되는 철골 모멘트골조와 가새의 내진보강 효과를 검증하였다. 해석결과에 따르면 $H150{\times}150{\times}6{\times}8$로 구성된 철골 모멘트골조는 탄성구간에서는 하중의 약 1%, 구조물이 항복한 이후, 최대 3.5%까지 하중을 부담하여 자체적으로 지진하중에 대한 저항 성능은 크지 않았다. 그러나 철골 모멘트골조와 가새를 동시에 사용함으로써 접합부의 조기 파괴를 방지하고 구조물의 내진성능을 큰 폭으로 증진시킬 수 있는 것으로 나타났다.

• Journal of the Earthquake Engineering Society of Korea
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• v.9 no.3 s.43
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• pp.77-85
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• 2005

After the collapse of the World Trade Center in september 11, 2001 and due to the frequent fire-caused damages of buildings during earthquake attacks, social concerns have been increased for the fire proof of the structural members of buildings. Recently, researches have been conducted to improve the fire resistance for building members not by the traditional ways but by utilizing the fire-resisting characteristics of reinforced concrete and structural characteristics of H-steel. In this paper, laboratory tests were conducted in room temperature to investigate the structural performance of the composite beams, which were developed to improve the fire resistance, comprising with concrete incasement between upper and lower flanges of H steel. From the experimental results, the displacement ductility factors of $6\~8$ were obtained. The difference of flexural behavior ol H steel-partial concrete incased composite beams with various composite details seems to be minor. The amount of longitudinal rebars is the most influential factor for the flexural strength of the composite beams. Therefore, if this type of composite beams are selected for designing a building located in moderate seismic lone, identical beam size could be used in several stories of the building.

• Journal of the Korea Concrete Institute
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• v.27 no.4
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• pp.451-458
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• 2015

The infill-wall strengthening method has been widely used for the seismic performance enhancement of the conventional reinforced concrete (RC) frame structures with non-seismic detail, which is one of the promising techniques to secure the high resisting capacity against lateral forces induced by earthquake. During the application of the infill-wall strengthening method, however, it often restricts the use of the structure. In addition, it is difficult to cast the connection part between the wall and the frame, and also difficult to ensure the shear resistance performances along the connection. In this study, an advanced strengthening method using the externally-anchored precast wall-panel (EPCW) was proposed to overcome the disadvantages of the conventional infill-wall strengthening method. The one-third scaled four RC frame specimens were fabricated, and the cyclic loading tests were conducted to verify the EPCW strengthening method. The test results showed that the strength, lateral stiffness, energy dissipation capacity of the RC frame structures strengthened by the proposed EPCW method were significantly improved compared to the control test specimen.

• Journal of the Korea Society for Simulation
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• v.27 no.1
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• pp.101-109
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• 2018

Field experiments as well as numerical analyses with finite element analysis codes are two valuable and complemental ways to understand the structural response under explosive blast load. However, there seems to be only limited information available about finite element analysis and experimental validation on the response of structural components under internal explosions. For complementary use of the two ways, the numerical analyses should be validated with field experiments by comparing their results. In this paper, a small-scaled reinforced concrete building with a room is employed for experimental investigations. An amount of TNT is detonated at the center of the room. Pressure at three different sites in the room, displacement of centers of two walls, and damage patterns of four walls are measured and compared to results from numerical analyses. The experimental results are much similar to the numerical analyses results. The finite element analysis code ANSYS AUTODYN is employed to numerically analyze both pressure distribution inside the room and response of walls subjected to blast pressure. The feasibility and validity of the numerical analysis on the reponses of structural components under internal explosions are discussed in terms of structural damage assessment, and evaluated as the same damage in the analysis and the experiments.

• Proceedings of the Korea Concrete Institute Conference
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• 1993.04a
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• pp.219-224
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• 1993

본 연구는 철근콘크리트 격납구조물에서 가상의 냉각제 유출사고에 의한 온도하중과 압력에 따른 거동을 알아보기 위한 비선형 해석을 수행하였다. 시간에 따른 온도하중을 결정하기 위하여 과도온도해석을 통해 격납구조물 단면내의 온도분포를 구하였다. 구조물은 기하학적 비선형성과 재료비선형성을 고려한 판 및 쉘요소로 이상화되며, 쉘요소는 두께방향에 따라 변하는 응력을 고려하기 위해 몇 개의 층으로 이루어진 모델을 사용하였다. 열응력은 인접한 두시간 단계에서의 온도차를 하나의 하중증가로 고려하여 초기변형 문제로 변환하여 결정되었다. 본연구에서의 수치실험에 의하여 과도온도해석에 근거한 비선형온도경사를 고려할 때의 변위가 고려하지 않을 때의 변위에 비해 크게 나타남을 알 수 있다.

• Proceedings of the Korea Concrete Institute Conference
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• 2009.05a
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• pp.99-100
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• 2009

In this paper, wish to achieve an experimental study to investigate enhanced performance of the masonry walls strengthened in shear and ductility using Aramid fiber strip.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.11a
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• pp.105-108
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• 2005

In damage investigation of building structures suffering from earthquake, estimation of residual seismic capacity is essential in order to access the safety of the building against aftershocks and to judge the necessity of repair and restoration. It has been proposed that an evaluation method for post-earthquake seismic capacity of reinforced concrete buildings based. on the residual energy dissipation capacity (the residual seismic capacity ratio )in lateral force-displacement curve of structural members. The proposed method was adopted in the Japanese 'Damage Level Classification Standard' revised in 200l. To evaluate the residual seismic capacity of RC column, experimental tests with positive and negative cyclic loading was carried out using RC building column specimen. Parameters used by the experiment are deformability and member proportion. From the test results, it is appropriated that the residual seismic capacity of RC buildings damaged by earthquakes is evaluated using the method in the Guideline.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.05a
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• pp.223-226
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• 2005

The purpose of this study is to discuss how strength and ductility of each system in low-rise R/C buildings combined with extremely brittle, shear and flexural failure systems have influence on seismic capacities of the overall system, which is based on seismic response analysis of SDOF structural systems. To simulate the triple lateral-load resisting system, structures are idealized as a parallel combination of two modified origin-oriented hysteretic models and degrading trilinear hysteretic model that fail primarily in extremely brittle, shear and flexure, respectively. Stiffness properties of three models are varied in terms of story shear coefficients, and structures are subjected to two ground motion components. By analyzing these systems, interaction curves of required strengths of the triple systems for various levels of ductility factors are finally derived for practical purposes.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2009.04a
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• pp.513-516
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• 2009

본 논문에서는 사례연구를 통하여 RC구조 BIM에서의 물량정보 획득의 효율성을 분석하고 이를 기반으로 BIM 프로세스 환경에서의 철근 및 콘크리트 물량산출을 위한 데이터베이스를 구축하여 현장 시공단계에서의 공정 및 물량관리의 협업단계를 가능하도록 하는 철근 Sorting 시스템에 대한 연구를 목적으로 한다. 기존의 건설, 건축분야에서의 정보는 기호적 언어와 2차원 기반의 도면 정보체계를 통해 표현되었지만, BIM 기술을 통해 건물의 실제 형상과 정보를 가지는 3차원 기반의 정보체계로의 변화와 함께 컴퓨터 데이터베이스 내에서 프로젝트에 포함된 모든 정보를 저장하고, 다양한 형태로 필요에 따라 정보를 표현할 수 있게 변화하고 있다. 견적 및 시공을 위한 RC구조설계단계에서의 배근 모델은 협업을 위한 객체 정보의 획득 및 추출이 중요하지만 현재 상용되고 있는 BIM도구에서는 현재까지 미흡한 체계를 이루고 있다. 본 논문에서는 구조설계를 기반으로 배근된 BIM 구조모델 사례를 통하여 기존 BIM도구에서의 물량 정보획득 효율성 분석을 기반으로 객체들의 데이터베이스 구축을 통한 철근 Sorting 시스템 구축 연구를 통하여 협업단계에서의 체계적 물량정보 관리를 가능하도록 하였다.

• Journal of the Korea Concrete Institute
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• v.19 no.5
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• pp.529-537
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• 2007

The purpose of this study is to discuss how strength and ductility of each system in low-rise reinforced concrete buildings composed of extremely brittle, shear and flexural failure lateral-load resisting systems have influence on seismic capacities of the overall system, which is based on nonlinear seismic response analyses of single-degree-of-freedom structural systems. In order to simulate the triple lateral-load resisting system, structures are idealized as a parallel combination of two modified origin-oriented hysteretic models and a degrading trilinear hysteretic model that fail primarily in extremely brittle, shear and flexure, respectively. Stiffness properties of three models are varied in terms of story shear coefficients, and structures are subjected to various ground motion components. By analyzing these systems, interaction curves of demand strengths of the triple system for various levels of ductility factors are finally derived for practical purposes. The result indicates that demand strength levels derived can be used as a basic information for seismic evaluation and design criteria of low-rise reinforced concrete buildings having the triple lateral-load resisting system.