• Coupled systems mechanics
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• 제5권2호
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• pp.127-144
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• 2016

Two dimensional numerical investigations were carried out to study the influence of interface thickness and their pattern on the behavior of reinforced concrete frames subjected to in-plane lateral loads using commercial finite element tool SAP 2000. The linear elastic analysis was carried out on one and two bay structural systems as well as the influence of number of stories was studied by varying the number of stories as single, three and five. The cement mortar was used as interface material and their effect was studied by varying thicknesses as 6, 8, 10, 14 and 20 mm. The interface was recognized as one sided, two sided, three sided and four sided and their effect was studied by removing the interface material between the reinforced concrete frame and masonry infill. The effect of lateral loads on infill masonry wall was also studied by varying assumed loads as 10, 20, 30, 40, 50 and 60 kN. The behavior of infilled frames studied has revealed that there is a maximum influence of interface thickness and interface pattern corresponding to 10 mm thickness. In general, the lateral displacement of frame is increased linearly with increase in lateral loads.

• 한국주거학회:학술대회논문집
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• 한국주거학회 2009년도 추계학술발표대회 논문집
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• pp.146-150
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• 2009

Present family pattern of Korean society has been changed into nuclear family pattern based on the married couple from traditional expanded family pattern. As the entire social consciousness has been changed into private disposition, the number of independent household for 1 person has increases. Also, as the delivery age of first child became late according to the elongation of average period for the national education, the increment of average age for the first marriage and women's participation in the society, the family pattern of married couple lasts longer than used to be. Like this, considering the family formed period comprised from a household for 1 person to a household for 1married couple and senescence increase, as any response is inevitable for the requirement of residential space where 1~2 dwellers' life can be accepted economic and functionally within smaller scaled space, development and research on a plan system(flexible-typed plan) increasing the degree of freedom is required in developing plan of unit household. In the study for this, considering the change of population and social structure, I suggest the method in developing economic design responding to the differentiation, designing the change of support-system and infill-system based on the systemic comprehension about the residing environment in the family formation period and the research for main life pattern and residing environment in the family formation period in the present city life. I will set (family) composing system, develop basic and mixing typed standard model and establish the stage of applied development for the development of economic design.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2008년도 추계 학술발표회 제20권2호
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• pp.89-92
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• 2008

최근 빈번하게 발생되는 지진으로 인해 내진규정이 강화된 바 있으며, 국내에서도 인접 국가들의 지진피해 발생으로 인해 지진에 대한 안전지대가 될 수 없다는 인식이 고조되어 건축구조설계기준에 서의 내진규정이 강화되었다. 그러나 기존 비내진상세를 갖는 건축물을 해체하여 요구성능을 얻고자 하는 경우 경제적, 환경적 손실이 크므로 비내진상세를 갖는 라멘구조물을 끼움벽을 통해 보강하는 것이 합리적일 것이라 판단된다. 따라서 본 연구에서는 변형경화형 시멘트 복합체인 SHCC를 끼움벽에 적용하였으며, 일반배근 및 대각보강근에 따른 내진성능을 정량적으로 평가함으로써 SHCC 적용에 따른 배근상세 감소 및 시공성 향상을 꾀하고자 한다. 실험체는 1/3 축소모형의 프리캐스트 끼움벽으로 제작되었으며, 실험결과 다수의 미세균열이 발생하여 기존 콘크리트에서 발생되는 명확한 전단균열 및 급격한 내력저하는 발생하지 않았다. 이는 SHCC 내 혼입된 PVA 및 PE 섬유의 가교작용에 의한 것으로 벽체에 전달되는 횡하중에 의한 응력을 재분배했기 때문인 것으로 사료된다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1999년도 봄 학술발표회 논문집
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• pp.399-406
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• 1999

Recently, the construction of the several highway bridges in the karst area have encountered severe problems associated with cavities and sinkholes. To solve this problems, it is important to understand the distribution characteristics of cavities in the construction site on limestone area. This paper briefly describes the different types, the distribution control factors and the infill sediment types of lime-cavities in the study area, bridge site in the karst area and propose the effective method of survey design. Cavity system may be divided into two main groups, 1)'slot and cave system'and 2)'sinkhole and cave system'. And the shape, the size and the distribution pattern of cavity are controlled by three main factors - rock type, geological structure and ground water condition. Additionally, infill sediment may be considered as one of the important design factors for foundation design and divided into four types by sediment properties. There are geophysical thechnics and geologic survey and drilling test, etc. by the survey method to interpretate characteristics of cavity system, and this methods are optimally designed at the site investigation stage.

• 콘크리트학회논문집
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• 제21권3호
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• pp.327-335
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• 2009

지진이 빈번하게 발생하는 지역에서는 비내진상세구조물은 지진 발생시 연약층을 형성하고 취성적 붕괴를 일으키게 된다. 그러나, 기존 구조물을 해체하고 내진상세 구조물을 신축하는 방법은 건설폐기물, 환경오염 및 민원 등 여러가지 문제들을 가지는 등 비경제적 방법이라 할 수 있다. 따라서 기존 구조물이 내진성능을 만족하도록 내진보강에 관한 많은 연구가 이루어졌으며, 이러한 내진보강방법에는 끼움벽, 철골브레이스, 연속벽, 부벽, 날개벽, 기둥/보의 자켓팅 등이 있다. 이 중 끼움벽 골조는 큰 변형과 접합부에서의 회전이 발생하는 골조와, 비교적 작은 변형에서도 전단파괴를 야기하는 끼움전단벽 등 복합적인 거동특성을 나타낸다. 따라서, 이러한 시스템의 거동특성은 개개의 골조나 벽에서 나타나는 거동특성과 매우 다르게 된다. 본 연구에서는 끼움벽의 내진성능을 평가하고자 하였으며, 손상에너지의 효과적 흡수를 위해 변형경화형 시멘트 복합체 (SHCC)를 사용하였다. 실험은 1/3 축소모형의 끼움벽을 반복가력하는 것으로 계획하였다. 실험 결과, SHCC 끼움벽에서는 섬유의 가교작용을 통해 시멘트 복합체 내 응력을 재분배함으로써 미세균열이 발생하였으며, 강도 및 에너지소산능력이 우수한 것으로 나타났다.

• 국제강구조저널
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• 제18권4호
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• pp.1210-1218
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• 2018

A new type of earthquake-resisting element that consists of a steel plate shear wall with slits is introduced. The infill steel plate is divided into a series of vertical flexural links with vertical links. The steel plate shear walls absorb energy by means of in-plane bending deformation of the flexural links and the energy dissipation capacity of the plastic hinges formed at both ends of the flexural links when under lateral loads. In this paper, finite element analysis and experimental studies at low cyclic loadings were conducted on specimens with steel plate shear walls with multilayer slits. The effects caused by varied slit pattern in terms of slit design parameters on lateral stiffness, ultimate bearing capacity and hysteretic behavior of the shear walls were analyzed. Results showed that the failure mode of steel plate shear walls with a single-layer slit was more likely to be out-of-plane buckling of the flexural links. As a result, the lateral stiffness and the ultimate bearing capacity were relatively lower when the precondition of the total height of the vertical slits remained the same. Differently, the failure mode of steel plate shear walls with multilayer slits was prone to global buckling of the infill steel plates; more obvious tensile fields provided evidence to the fact of higher lateral stiffness and excellent ultimate bearing capacity. It was also concluded that multilayer specimens exhibited better energy dissipation capacity compared with single-layer plate shear walls.

• Structural Engineering and Mechanics
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• 제70권4호
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• pp.421-429
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• 2019

This paper presents an analytical model for the estimation of initial lateral stiffness of steel moment resisting frames with masonry infills. However, rather than focusing on the single bay-single storey substructure, the developed model attempts to estimate the global stiffness of multi-storey and multi-bay frames, using an assembly of equivalent springs and taking into account the shape of the lateral loading pattern. The contribution from each infilled frame panel is included as an individual spring, whose properties are determined on the basis of established diagonal strut macro-modeling approaches from the literature. The proposed model is evaluated parametrically against numerical results from frame analyses, with varying number of frame stories, infill openings, masonry thickness and modulus of elasticity. The performance of the model is evaluated and found quite satisfactory.

• Earthquakes and Structures
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• 제10권4호
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• pp.769-788
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• 2016

The present study aimed at investigating the effect of a special plaster on the out-of-plane behavior of masonry walls. A reference specimen, plastered with conventional plaster, and a specimen plastered with a special plastered were tested under reversed cyclic lateral loading. The specimens were identical in dimensions and material properties. The special plaster contained an additive, which increased the adherence strength of the plaster to the wall. The amount of the additive in the mortar was adjusted based on the preliminary material tests. The influence of the plaster on the wall behavior was evaluated according to the initial cracking load, type of failure, energy absorption capacity (modulus of toughness), and crack pattern of the wall. Despite having limited contribution to the ductility, the special plaster increased the ultimate load capacity of the wall about 25%. The failure mode of the wall with special plaster resembled the plastic failure mechanism of a reinforced concrete slab in the formation of yielding lines along the wall. The deflection at failure and the modulus of toughness of the wall with special plaster were measured to be in order of 60% and 75% of the corresponding values of the reference wall.