매립형 불완전 합성보의 휨 거동 예측

허병욱,배규웅,문태섭,Heo, Byung Wook,Bae, Kyu Woong,Moon, Tae Sup 한국강구조학회 2004 韓國鋼構造學會 論文集 Vol.16 No.6

강-콘크리트 합성보에서 강과 콘크리트 사이의 불완전 합성거동은 완전 합성보에 비해서 처짐이 매우 증가하게 된다. 특히, 춤이 깊은 데크 및 속 빈 PC슬래브 등을 사용한 매립형 합성보의 경우, 자체의 형상에 기인하여 처짐에 매우 취약하다. 본 연구에서는 기존 연구에서 유도한 슬립효과를 고려한 처짐 계산법 및 실험으로부터 구한 하중-슬립 관계로부터 매립형 합성보의 전단부착응력 및 슬립에 의한 추가 처짐 값을 제시하였다. 매립형 합성보의 처짐에 미치는 슬립의 영향은 완전 합성보의 강성 값에 비해 약 30%정도 감소함을 알 수 있었다. 또한, 실험 및 예측 값의 비교결과, 6%내외의 오차로 비교적 좋은 결과를 나타내었다. With steel and concrete composite beams, the incomplete interaction between the steel and the concrete slab leads to an appreciable increase in beam deflections. Moreover, encased composite beams using a deep deck plate or hollow-core PC slabs are critical to deflection due to their inherent geometry. In this paper, by using the calculation tools that were developed for a previous study on the deflection of encased composite beams considering the slip effects and load-slip curve, the shear bond stress and additional deflection induced due to interface slip of the encased composite beam are presented. It was found that the slip effects significantly contribute to the encased composite beam deflections and result in stiffness reduction of up to 30% compared to that of full shear interaction beams. The predicted results were compared with the measurement of 18 specimens tested in this study, and comparisons show a high degree of accuracy, within 6%.

전단슬립 효과 및 하중조건을 고려한 불완전 합성보의 유효강성

허병욱,배규웅 대한건축학회 2006 大韓建築學會論文集 : 構造系 Vol.22 No.11

The present study investigates the effects of shear slip on deflection of steel-concrete composite beams with partial shear interaction. According to the various current design codes, the deflection is related to the strength of shear connectors in the composite beams. However, the decrease of stiffness due to slip effects is not considered in the current design codes and relevant calculation tools for partial shear connection are not even presented. In this paper, an exact solution based on the stiffness of shear connectors is developed which is not dependent on the load cases. The equivalent rigidity of composite beams considering three different loading types was first derived based on equilibrium and curvature compatibility, from which a general formula to account for slip effects was developed.

매입형(슬림플로어) 합성보의 휨성능 평가 -춤이 깊은 데크플레이트와 비대칭 H형강 철골보-

허병욱,배규웅,문태섭,Heo, Byung Wook,Bae, Kyu Woong,Moon, Tae Sup 한국강구조학회 2004 韓國鋼構造學會 論文集 Vol.16 No.2

현재 합성 구조가 사용성 측면에서 경제적이고 작업성이 좋으며, 시공상의 편의성 등의 장점이 있다는 것은 일반화된 사실이지만, 자체의 춤이 깊기 때문에 철골조 건물에 적용하기에 여러 가지 비효율적 측면이 있다. 따라서 본 연구에서는 합성보의 전체 춤을 절감할 수 있도록 철골보의 춤내에 콘크리트를 삽입하여 일체화함으로써 철골조 고층건물에서 층고를 최소화 할 수 있는 이른바 "슬림플로어" 공법에 대한 연구를 수행하였다. 본 연구는 콘크리트에 매입된 비대칭 철골보를 가지는 부분 합성 슬림플로어 시스템의 휨거동에 관한 것이다. 총 8개의 실대형 실험체를 철골보 춤, 전단연결 유무, 슬래브 유효폭, 및 콘크리트 토핑두께 별로 제작하여 실험을 수행하였다. 실험결과, 별도의 전단연결재를 설치하지 않은 실험체는 자체가 가지고 있는 기계적 화학적 부착응력으로 인해 완전합성보에 비해서 $0.53{\sim}0.95$의 전단합성비를 나타내었다. The advantages of composite construction are now well understood in terms of structural economy, good performance in service, and ease of construction. However, these conventional composite construction systems have some problems in application to steel framed buildings due to their large depth. So, in this study we executed an experimental test with the "Slim Floor"system which could reduce the overall depth of composite beam. Slim Floor system is a method of steel frame multi-story building construction in which the structural depth of each floor is minimized by incorporating the steel floor beams within the depth of the concrete floor slab. Presented herein is an experimental study that focuses on the flexural behaviour of the partially connected slim floor system with asymmetric steel beams encased in composite concrete slabs. Eight full-scale specimens were constructed and tested in this study with different steel beam height, slab width, with or without shear connection and concrete topping thickness. Observations from experiments indicated that the degree of shear connection without additional shear connection was $0.53{\sim}0.95$ times that of the full shear connection due to inherent mechnical and chemical bond stress.

불완전 합성보의 유효강성 평가방법 비교

허병욱,배규웅 대한건축학회 2006 大韓建築學會論文集 : 構造系 Vol.22 No.11

Previously study, An exact solution based on the stiffness of shear connectors was developed which is not dependent on the load cases. The equivalent rigidity of composite beams considering three different loading types was first derived based on equilibrium and curvature compatibility, from which a general formula to account for slip effects was developed. To validate this approach, the predicted maximum deflection using the proposed method is compared against currently used equations for the calculation of the beam effective stiffness. For typical beams used in practice, shear slip effects may results in stiffness reduction up to 18% for short span beams. For full composite sections, the effective stiffness with the AISC specifications are larger than that of present study, meaning that the specifications are not on the conservation side. For partial composite sections, the AICS predictions are more conservative than the present study.

속빈 PC 슬래브와 채널을 사용한 매입형 합성보의 휨 거동

허병욱,곽명근,배규웅,Heo, Byung Wook,Kwak, Myong Keun,Bae, Kyu Woong 한국강구조학회 2008 韓國鋼構造學會 論文集 Vol.20 No.4

This paper deals with the experimental analysis of the flexural behaviour of encased composite beams with hollow core slabs and channels. The shear force between steel beams and hollow core slabs are transferred by channels. Three full-scale specimens were constructed and tested with different steel beam heights, which were compared with those of previous studies. Based on observation of the experiments, the encased composite beams exhibited full shear connection behaviour without any other shear connectors due to their inherent mechanical and chemical bond stress. Experimental results show a behaviour similar to steel-concrete composite beams with classical connectors: elastic and yield domains, great ductility, flexural failure mode (plastic hinge), low relative movement at steel-concrete interface and all specimens failed in a very ductile manner. Consequently, this study enables the validation of the proposed connection device under static loading and shows that it meets modern structural requirements. 본 연구는 속빈 PC 슬래브와 채널을 사용한 매입형 합성보의 휨거동에 관한 것이다. 철골보와 PC슬래브의 경계면에 발생하는 전단력은 채널에 의해서 전달된다. 철골보의 춤에 따라서 총 3개의 실대형 실험체를 제작하여 실험을 수행하였으며 기존에 수행된 전단접합 방식과 비교검토를 수행하였다. 채널 용접형 매입형 합성보의 실험결과, 별도의 전단연결재를 설치하지 않아도 자체가 가지고 있는 기계적?화학적 부착응력으로 인해 완전합성보에 가까운 거동을 나타내었다. 또한, 기존의 합성보의 거동과 같이 탄성구간, 항복구간, 매우 큰 연성, 휨파괴모드(소성힌지), 경계면에서의 매우 낮은 상대슬립 및 연성적인 파괴거동을 나타내었다. 따라서 제안된 전단연결 방식의 경우, 실제 건물에 적용시 규준에서 요구하는 구조적 성능을 만족할 수 있는 것으로 나타났다.

전단슬립 효과를 고려한 매입형 불완전 합성보의 휨거동

허병욱 대한건축학회 2007 大韓建築學會論文集 : 構造系 Vol.23 No.7

The advantages of composite construction are now well understood in terms of structural economy, good performance in service, and ease of construction. However, these conventional composite construction systems have some problems to apply steel framed buildings due to their large depth. Slim Floor system is a method of steel frame multi-story building construction in which the structural depth of each floor is minimised by incorporating the steel floor beams within the depth of the concrete floor slab. Previous study we executed an experimental test with “Slim Floor” system using hollow core PC slab and deep deck plate which could reduce the overall depth of composite beam. Presented herein is an analytical study that focuses on flexural behaviour of the partially connected slim floor system with asymmetric steel beams encased in slabs. From the comparison between the analytical study and the test results, It showed a good agreement with respect to the stiffness reduction due to shear slip. Finally, an equations to predict the load-deflection relationship of encased composite beam are presented.

트러스 데크를 사용한 강판성형 합성보의 휨성능 평가

허병욱,곽명근,배규웅,정상민,강석규,Heo, Byung Wook,Kwak, Myong Keun,Bae, Kyu Woong,Jung, Sang Min,Kang, Suk Kuy 한국강구조학회 2007 韓國鋼構造學會 論文集 Vol.19 No.4

기존의 층고절감형 합성보 시스템은 철골보의 웨브면에 바닥판을 삽입하여 시공하기 때문에 상대적으로 기존 합성보 형식과 비교하여 층고를 대폭적으로 줄일 수 있지만, 적용되는 철골보 춤이 제한되기 때문에 적용 가능한 스팬이 한정되어 있어 여러 가지 다양한 건축구조의 수요에 능동적으로 대처하기가 어려운 단점이 있다. 따라서, 본 연구에서는 기존의 층고절감형 합성보의 단점을 해결하기 위하여 합성보의 춤을 자유로이 조절할 수 있는 층고절감형 매입형 합성보를 개발하였다. 본 연구는 콘크리트에 매입된 강팡성형 철골보를 가지는 불완전 합성보의 휨거동에 관한 것이다. 총 5개의 실대형 실험체를 전단연결재 및 보강근의 사용유무, 슬래브 형식을 주요변수로 하여 실험을 수행하였다. 실험결과, 별도의 전단연결재를 설치하지 않은 실험체는 자체가 가지고 있는 기계적 화학적 부착응력으로 인해 $0.20{\sim}0.76N/mm^2$의 부착응력을 나타내었다. Slimfloor composite-beam systems could considerably reduce the story height of a building if the steel beam would be installed deep into the concrete floor slab. However, as the depth of the steel beam's installation is limited, it cannot cope with the various demands of building systems. To address this problem, a profiled steel beam section that can control the depth of the steel beam's and slabs' installation was developed in this study. Presented herein are the results of an experiment that was conducted focusing on the flexural behavior of the partially connected composite beams with profiled steel beams encased in composite concrete slabs. Five full-scale specimens with different slab types, with or without shear connection and reinforcement bars, were constructed and tested in this study. As a result, the shear bond stress without an additional shear connection was found to be $0.20{\sim}0.76N/mm^2$due to the inherent mechanical and chemical bond stress.

매입형 불완전 합성보의 휨거동에 대한 해석적 연구

허병욱,신현섭,배규웅 대한건축학회 2007 大韓建築學會論文集 : 構造系 Vol.23 No.6

With steel and concrete composite beams, the incomplete interaction between the steel and the concrete slab leads to an appreciable increase in beam deflections. Moreover, encased composite beams using a deep deck plate or hollow-core PC slabs are critical to deflection due to their inherent geometry. In this paper, by using the calculation tools that were developed for a previous study on the deflection of encased composite beams considering the slip effects and load-slip curve, the shear bond stress and additional deflection induced due to interface slip of the encased composite beam are presented. It was found that the slip effects significantly contribute to the encased composite beam deflections and result in stiffness reduction of up to 30% compared to that of full shear interaction beams. The predicted results were compared with the measurement of 18 specimens tested in this study, and comparisons showed a high degree of accuracy, within 6%.

강판성형 합성보의 휨성능 평가 -춤이 깊은 합성데크-

허병욱,곽명근,배규웅,정상민,Heo, Byung Wook,Kwak, Myong Keun,Bae, Kyu Woong,Jeong, Sang Min 한국강구조학회 2007 韓國鋼構造學會 論文集 Vol.19 No.3

본 논문은 철골보의 하부 플랜지의 높이 조절이 가능하여 합성바닥판의 춤이 자유로운 신형상의 매입형 합성보에 관한 실험적 연구이다. 이를 위하여 강판성형 철골보 단면을 개발하였고 바닥 슬래브용으로 250mm의 춤을 가진 춤이 깊은 데크 플레이트(이하 Deep Deck)를 사용하여 장스팬에 유리하도록 계획하였다. 실험은 전단스터드 및 인장보강근의 사용유무, 사용강판의 두께, 웨브 개구부의 유무를 주요 변수로 하여 총 7개의 매입형 합성보에 대한 단순지지 휨실험 수행하였다. 실험결과, 강판성형 매립형 합성보는 전단연결재의 설치 없이 철골보와 콘크리트의 부착력에 의해 수평전단력이 전달되는 방식임에도 불구하고 대단히 우수한 합성거동을 나타냄을 확인하였다. This paper describes the results of an experimental study on the new type of encased composite beams that use deep deck plates, which could reduce the story height of buildings by controlling the bottom flange of steel beams. The profiled steel beam was thus developed. It was advantageous to the long span of the buildings. Seven full-scale specimens were constructed, and simply supported bending tests were conducted on the encased composite beams with different steel plate thicknesses, with and without shear studs, reinforcing bars, and web openings. The test results showed that the encased composite beams that were developed in this study had sufficient composite action without additional shear connectors due to their inherent shear-bond effects between the steel beams and concrete.

강-콘크리트 불완전 합성보의 처짐평가

허병욱,곽명근,배규웅 大韓建築學會 2007 大韓建築學會論文集 : 構造系 Vol. No.

<P>The present study investigates the effects of shear slip on deflection of steel-concrete composite beams with partial shear interaction. According to the various current design codes, the deflection is related to the strength of shear connectors in the composite beams. However, the decrease of stiffness due to slip effects are not considered in the current design codes and relevant calculation tools for partial shear connection are not even presented. In previous study, It is derived an exact solution based on the stiffness of shear connectors which is not dependent on the load cases. The equivalent rigidity of composite beams considering three different loading types was first derived based on equilibrium and curvature compatibility, from which a general formula to account for slip effects was developed. To validate this approach, the predicted maximum deflection using the proposed method and currently used equations for the calculation of the beam effective stiffness is compared against test results. From the comparison between test results and analytical study, it is found that the stiffness of a composite beam based on the strength of shear studs is considerably over-estimated. The stiffness of composite beams is predicted accurately with the method proposed in this study.</P>