• 한국전산구조공학회논문집
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• 제15권1호
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• pp.165-172
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• 2002

일반적으로 모멘트 지지 강구조물은 유한요소법에 의해 이상화되고 해석되어 왔으며 기둥과 기둥의 연결부, 기둥과 보의 접합부의 정확한 비선형 해석 결과를 위해 많은 노력을 해온 반면에 기둥의 지지부에 대한 해석은 고정단 또는 힌지로 간단하게 이루어져 왔다 그러나 실제로 기둥의 지지부는 고정단도 힌지도 아닌 그 중간인 반강성으로 거동한다. 본 논문에서는 이러한 기둥 지지부를 반강성모델을 이용해서 해석하고 그 결과를 고찰하여 기둥 지지부의 강성 및 강도의 변화가 미치는 영향을 평가하였다. 미국 시방서에 의해 설계된 전형적인 두개의 3층 모멘트지지 강구조물을 이미 개발된 강성도법 및 유연도법에 기초한 7iber 유한 요소를 사용하여 해석하였다. 기등의 지지부는 고정단과 힌지사이에 있는 반강성 지지부를 모델하기 위해 다양한 강성도를 갖는 회전 스프링을 사용하였다. 실제의 기둥 지지부와 가깝게 모델된 반강성 지지부를 갖는 구조물의 해석 결과는 고정지지부를 갖는 구조물과 어느 정도 비슷한 결과를 보여주었다. 또한 pushover 해석과 비선형 시간 이력 해석을 통해 기둥 지지부의 강성도가 감소함에 따라 1층 보의 소요 처짐각(rotational demand)이 증가하는 현상이 관찰되었다 시공상의 문제 및 노화로 인한 기동 지지부의 강성도 감소는1층의 접합부에 대한 소요 터짐각의 증가를 유발하고 그것은 곧 soft-story mechanism을 유발하게 된다.

• 한국전산구조공학회논문집
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• 제22권4호
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• pp.355-362
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• 2009

국내에 많이 건설되고 있는 빌라형 주택은 건축적인 요구를 위하여 저층부에 필로티를 두고 있는 경우가 많다. 구조물 상층부의 비내력벽에 의하여 저층에 연약층을 유발하고 따라서 지진에 매우 취약하다. 그러나 설계시 일반적인 설계방법과 동일하게 상부층의 칸막이벽은 비구조체로 간주되어 무시된다. 그러므로 설계단계에서 무시되는 비내력벽의 유무에 따라서 건축물이 어떠한 지진거동의 차이점을 보이는지 살펴볼 필요가 있다. 본 연구에서는 대상 건축물의 지진취약도 해석을 통하여 비내력벽의 유무에 따른 건축물의 지진거동을 평가하였다. 비내력벽의 유무에 따른 동일한 골조를 가지는 저층 철근콘크리트 건축물을 적용하여 지진거동에서 비내력벽의 영향을 평가하였다. 비내력벽은 보편화된 모형화 방법인 등가의 대각 압축 스트럿으로 고려하였다. 골조만 있는 모델과 연약층이 있는 모델의 취약도곡선을 비교하였다. 해석 결과로 연약층이 있는 RC 건물의 내진성능은 설계기준에서 제시하고 있는 성능수준을 만족하지 못하며 지진에 취약함을 보여준다.

• Structural Engineering and Mechanics
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• 제51권1호
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• pp.89-110
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• 2014

In this study, two beam-column elements based on the Elasto-Fiber element theory for reinforced concrete (RC) element have been developed and compared with each other. The first element is based on Elasto Fiber Approach (EFA) was initially developed for steel structures and this theory was applied for RC element in there and the second element is called as Fiber & Bernoulli-Euler element approach (FBEA). In this element, Cubic Hermitian polynomials are used for obtaining stiffness matrix. The beams or columns element in both approaches are divided into a sub-element called the segment for obtaining element stiffness matrix. The internal freedoms of this segment are dynamically condensed to the external freedoms at the ends of the element by using a dynamic substructure technique. Thus, nonlinear dynamic analysis of high RC building can be obtained within short times. In addition to, external loads of the segment are assumed to be distributed along to element. Therefore, damages can be taken account of along to element and redistributions of the loading for solutions. Bossak-${\alpha}$ integration with predicted-corrected method is used for the nonlinear seismic analysis of RC frames. For numerical application, seismic damage analyses for a 4-story frame and an 8-story RC frame with soft-story are obtained to comparisons of RC element according to both approaches. Damages evaluation and propagation in the frame elements are studied and response quantities from obtained both approaches are investigated in the detail.

• Earthquakes and Structures
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• 제26권6호
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• pp.463-475
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• 2024

The study aims to investigate the pounding that occurs between the isolator's ring and slider of isolated structures resulting from excessive seismic excitation, while considering soil-structure interaction. The dynamic responses and poundings of structures subjected a series seismic records were comparatively analyzed for three different soil types and fixed-base structures. A series of parametric studies were conducted to thoroughly discuss the effects of the impact displacement ratio, the FPB friction coefficient ratio, and the radius ratio on the structural dynamic response when considering impact and SSI. It was found that the pounding is extremely brief, with an exceptionally large pounding force generated by impact, resulting in significant acceleration pulse. The acceleration and inter-story shear force of the structure experiencing pounding were greater than those without considering pounding. Sudden changes in the inter-story shear force between the first and second floors of the structure were also observed. The dynamic response of structures in soft ground was significantly lower than that of structures in other ground conditions under the same conditions, regardless of the earthquake wave exciting the structure. When the structure is influenced by pulse-type earthquake records, its dynamic response exhibits a trend of first intensifying and then weakening as the equivalent radius ratio and friction coefficient ratio increase. However, it increases with an increase in the pounding displacement ratio, equivalent radius ratio, friction coefficient ratio, and displacement ratio when the structures are subjected to non-pulse-type seismic record.

• 한국지진공학회논문집
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• 제28권3호
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• pp.149-158
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• 2024

Piloti-type structures with vertical irregularity are vulnerable to earthquakes due to the soft structure of the first story. Structural characteristics of buildings can significantly affect the seismic loss function, calculated based on seismic fragility, and therefore need to be considered. This study investigated the effects of the number of stories and core locations on the seismic loss function of piloti-type buildings in Korea. Twelve analytical models were developed considering two variations: three stories (4-story, 5-story, and 6-story) and four core locations (center core, x-eccentric core, y-eccentric core, and xy-eccentric core). The interstory drift ratio and peak floor acceleration were assessed through incremental dynamic analysis using 44 earthquake records, and seismic fragility was derived. Seismic loss functions were calculated and compared using the derived seismic fragility and repair cost ratio of each component. The results indicate that the seismic loss function increases with more stories and when the core is eccentrically located in the piloti-type structure model. Therefore, the uncertainty due to the number of stories and core location should be considered when deriving the seismic loss function of piloti-type structures.

• 한국콘텐츠학회논문지
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• 제13권12호
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• pp.1006-1016
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• 2013

본 연구는 수단-목적 사슬이론을 적용하여 엔터테인먼트관광자가 추구하는 가치를 규명하고자 하였다. 자료 수집은 2012년 7월부터 10월까지 제주에서 하였다. 연구의 절차는 먼저, 소프트 래더링기법을 실시하기 위하여 공연을 관람한 관광자와 일대일 심층인터뷰를 실시하였으며, 소프트 래더링의 결과를 바탕으로 내용분석을 하였다. 둘째, 내용분석의 결과에 의한 함축매트릭스 결과표를 제시하였으며, 이를 통해 최종적으로 엔터테인먼트관광자의 가치맵(HVM)을 작성하였다. 연구결과 엔터테인먼트관광자의 가치는 미적가치, 타인과의 소통, 즐거움 등으로 나타났다. 특히 지배적 가치는 즐거움으로 나타났는데, 이의 가치체계는 속성의 재미, 혜택의 감각적 즐거움 등의 연결 구조를 가지고 있었다. 이와 같은 결과는 엔터테인먼트관광자가 놀이적 인간(homo ludens)임을 지지하는 것으로, 엔터테인먼트관광의 공급은 스토리-텔링(story-telling)보다 스토리-왓칭(story-watching)에 더 집중할 필요가 있음을 시사하고 있다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2007년 가을학술발표회
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• pp.78-89
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• 2007

Two design examples of deep foundations for high-rise buildings on soft ground are introduced in this paper. The first one is a 54-story building in Ho-Chi-Minh city, Vietnam, which was designed to be founded on $2.8m{\times}1.0m$ barrette foundations with approximately 60m to 75m depth. Based on a number of design guides and existing load test data from the construction sites in Ho-Chi-Minh city, the capacity of a barrette foundation in sand or clay layered ground was calculated to be 17.2MN to 27.8MN depending on the installing depth. The second one is a 40-story building in Baku city, Azerbaijan, which was designed to be supported by 2.0m diameter bored pile foundations with approximately 23m depth. As analytical or empirical guides for the local ground conditions were very limited, the design procedure from the SNiP Code, one of Russian specifications, was adopted and used to calculate the pile capacity. The capacity of bored pile foundation in highly weathered soil was expected to be 14.8MN to 15.5MN depending on the boring depth.

• 국제초고층학회논문집
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• 제3권3호
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• pp.199-204
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• 2014

W-Project is 70-story mixed-use residential building complex project in Busan, the second biggest city in South Korea. As it is a high rise building complex located at the coast, the residents have great ocean view from the height. Though, there were many difficult challenges to be solved to secure structural safety and meet the serviceability requirements. As it is located on the reclaimed land, securing the foundation bearing capacity on soft soil is the first issue to be solved for the stable structure. W-Project. Busan on the way usual track of typhoon, wind load on structure is also critical for structural safety and serviceability for occupants due to wind vibration. This paper will address process of lateral load resisting structural system of W-Project.

• 국제초고층학회논문집
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• 제2권2호
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• pp.141-152
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• 2013

This paper presents a brief overview of the recently developed performance-control method of moment frame design subjected to monotonously increasing lateral loading. The final product of any elastic-plastic analysis is a nonlinear loaddisplacement diagram associated with a progressive failure mechanism, which may or may not be as desirable as expected. Analytically derived failure mechanisms may include such undesirable features as soft story failure, partial failure modes, overcollapse, etc. The problem is compounded if any kind of performance control, e.g., drift optimization, material savings or integrity assessment is also involved. However, there is no reason why the process can not be reversed by first selecting a desirable collapse mechanism, then working backwards to select members that would lead to the desired outcome. This article provides an overview of the newly developed Performance control methodology of design for lateral resisting frameworks with a view towards integrity control and prevention of premature failure due to propagation of plasticity and progressive P-delta effects.

• Structural Engineering and Mechanics
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• 제88권6호
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• pp.535-549
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• 2023

Deep extreme learning machine (DELM) and multi-verse optimization algorithms (MVO) are hybridized for designing an optimal and adaptive control framework for uncertain buildings. In this approach, first, a robust model predictive control (RMPC) scheme is developed to handle the problem uncertainty. The optimality and adaptivity of the proposed controller are provided by the optimal determination of the tunning weights of the linear programming (LP) cost function for clustered external loads using the MVO. The final control policy is achieved by collecting the clustered data and training them by DELM. The efficiency of the introduced control scheme is demonstrated by the numerical simulation of a ten-story benchmark building subjected to earthquake excitations. The results represent the capability of the proposed framework compared to robust MPC (RMPC), conventional MPC (CMPC), and conventional DELM algorithms in structural motion control.