• Steel and Composite Structures
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• 제33권4호
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• pp.569-581
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• 2019

Corrugated steel plate shear wall (CSPSW) as an innovative lateral load resisting system provides various advantages in comparison with the flat steel plate shear wall, including remarkable in-plane and out-of-plane stiffnesses and stability, greater elastic shear buckling stress, increasing the amount of cumulative dissipated energy and maintaining efficiency even in large story drifts. Employment of low yield point (LYP) steel web plate in steel shear walls can dramatically improve their structural performance and prevent early stage instability of the panels. This paper presents a comprehensive structural performance assessment of corrugated low yield point steel plate shear walls having circular openings located in different positions. Accordingly, following experimental verification of CSPSW finite element models, several trapezoidally horizontal CSPSW (H-CSPSW) models having LYP steel web plates as well as circular openings (for ducts) perforated in various locations have been developed to explore their hysteresis behavior, cumulative dissipated energy, lateral stiffness, and ultimate strength under cyclic loading. Obtained results reveal that the rehabilitation of damaged steel shear walls using corrugated LYP steel web plate can enhance their structural performance. Furthermore, choosing a suitable location for the circular opening regarding the design purpose paves the way for the achievement of the shear wall's optimal performance.

• Computers and Concrete
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• 제26권1호
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• pp.95-106
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• 2020

Castellated beams fabricated from standard I-sections are being used for several structural applications such as commercial and industrial buildings, multistory buildings, warehouses and portal frames in view of numerous advantages. The advantages include enhanced moment of inertia, stiffness, flexural resistance, reduction in weight of structure, by passing the used plate girders, the passage of service through the web openings etc. In the present study, experimental and numerical investigations were carried out on concrete encased steel castellated beams with hexagonal openings under flexural loading. Various positions of openings such as along the neutral axis, above the neutral axis and below the neutral axis were considered for the study. From the experimental findings, it has been observed that the load-carrying capacity of the castellated beam with web opening above neutral axis is found to be higher compared to other configurations. Nonlinear finite element analysis was performed by using general purpose finite element software ABAQUS considering the material nonlinearities. Concrete damage plasticity model was employed to model the nonlinearity of concrete and elasto-plastic model for steel. It has been observed that FE model could able to capture the behaviour of concrete encased steel castellated beams and the predicted values are in good agreement with the corresponding experimental values.

• 한국구조물진단유지관리공학회 논문집
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• 제25권2호
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• pp.66-73
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• 2021

유공 강재보에 대한 기존연구는 개구부의 위치가 강재보의 지지점까지의 이격이 보 단면 높이 이상인 경우가 다수이다. 유공 강재보의 개구부를 사용하는 덕트 및 배관 등의 설비시설의 배치를 고려할 때, 개구부는 강재보 지지점까지 이격이 보 단면 높이보다 가까운 경우가 있으므로 이에 대한 연구의 필요성이 대두된다. 본 연구는 지지점에 근접하게 개구부가 설치된 유공 강재보에 반복하중 가력에 따른 구조성능을 파악하는 실험연구이다. 또한 유공 강재보에 수직·수평 강판을 이용한 개구부 보강에 대하여 실험을 통하여 보강성능을 파악하고자 한다.

• International Journal of Concrete Structures and Materials
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• 제4권2호
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• pp.77-87
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• 2010

Prestressed concrete (PSC) I-type girders have been used for span length around up to 40 m in domestic region. PSC girders are very cost effective girder type and extending their lengths more than 50 m will bring large benefit in cost. A new design method was proposed by combining two notable design concept in order to extend the applicable span length in this study. First of all, several numbers of openings was introduced in the girder web, and half of the anchorage devices were moved into the openings. In this way, large compressive stress developed at end zone was reduced, and the portion of design load coming from self-weight was reduced as well. Secondly, prestressing force was introduced in the girder not once at the initial stage, but through multiple loading stages. A full scale girder with the length of 50 m with the girder depth of 2 m was fabricated, and a flexural test was conducted in order to verify the performance of newly developed girder. Test results showed that the new holed web design concept can provide a way to design girders longer than 50 meters with the girder height of 2 m.

• Structural Engineering and Mechanics
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• 제4권4호
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• pp.437-450
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• 1996

A study on the behaviour of fibre reinforced concrete deep beams with and without web openings is carried out using nonlinear finite element analysis. Eight node isoparametric plane stress elements are employed to model the fibre reinforced concrete materials. Steel bars are treated using a compatible three node truss elements. The constitutive equations for fibre reinforced concrete materials take into account the softening effect of co-existing shear strains. Element stiffness at each step is formulated based on the tangent modulus at the current level of principal strains. Transformation between principal directions and global coordinate system is imposed. Comparison of analytical results with experimental values indicates reasonably good agreement. The proposed numerical model can be used to study the behaviour of this composite structures of practically any geometries.

• Structural Engineering and Mechanics
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• 제84권3호
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• pp.311-321
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• 2022

In the buildings with long spans and high floors, such as logistics warehouses and semiconductor factories, it is difficult to install supporting posts under beams during construction. Therefore, the size of structural members becomes larger inevitably, resulting in a significant increase in construction costs. Accordingly, a prestressed hybrid wide flange (PHWF) beam with hollowed steel webs was developed, which can reduce construction costs by making multiple openings in the web of the steel member embedded in concrete. However, since multiple openings exist and prestress is introduced only into the bottom flange concrete, it is necessary to identify the shear resistance mechanism of the PHWF beam. This study presents experimental shear tests of PHWF beams with hollowed steel webs. Four PHWF beams with cast-in-place (CIP) concrete were fabricated, with key variables being the width and spacing of the steel webs embedded in the concrete and the presence of shear reinforcing bars, and web-shear tests were conducted. The shear behavior of the PHWF beam, including crack patterns, strain behavior of steel webs, and composite action between the prestressed bottom flange and CIP concrete, were measured and analyzed comprehensively. The test results showed that the steel web resists external shear forces through shear deformation when its width is sufficiently large, but as its width decreased, it exerted its shear contribution through normal deformation in a manner similar to that of shear reinforcing bars. In addition, it was found that stirrups placed on the cross section where the steel web does not exist contribute to improving the shear strength and deformation capacity of the member. Based on the shear behavior of the specimens, a straightforward calculation method was proposed to estimate the web-shear strength of PHWF beams with CIP concrete, and it provided a good estimation of the shear strength of PHWF beams, more accurate than the existing code equations.

• 한국강구조학회 논문집
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• 제13권2호
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• pp.177-189
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• 2001

현대 건축물들의 고층화 추세에 따라 등장한 구조물의 공사비 절감을 위한 한 방법으로 H형강보의 웨브 부분에 설비용 덕트와 배관류 등을 관통시키기 위하여 개구부를 두는 유공보를 자주 사용하고 있다. 본 연구에서는 현재 유공보의 설계에 사용되고 있는 기존의 강도식들의 문제점을 살펴보고 소성 붕괴 매커니즘에 기초를 둔 보다 합리적인 강도식을 제안하고자 한다. 제안식은 기존의 강도식들과 비교하여 볼 때 단순하며 이해하기 쉽다. 제안식의 검증은 과거에 이루어진 연구 결과들을 사용하여 평가되어 졌다. 이들 연구결과들을 근거로 제안식의 극한 강도를 비교해 볼 때 현재 실무에서 사용되어 지고있는 강도식들보다 합리적인 결과 값을 기대할 수 있다.

• 산업기술연구
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• 제21권A호
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• pp.7-14
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• 2001

In building structure, the story height can be minimized by providing openings in beams which serves for the utility equipments passing through. The dead space in false ceiling thus put to economical use in the form of a substantial reduction in materials and construction cost. In the case of steel structure, there is no critical risk in the structural strength because of reinforcing methods of stiffness and steel plate but in the case of reinforced concrete structure, proper provision should be made in designing these openings, otherwise there is a risk that these opening will possibly weaken the structural strength of the building frame to a critical degree. In this paper, for the numerical analysis of the reinforced concrete beams with circular opening in the web, expecting stress concentration of the circular opening, reinforcing methods were studied. Twenty test pieces with each different reinforcing methods were tested and their resisting forces were defined. From the numerical analysis and test results, the followings were founded;(1)high shear stress distributed around the openings reduce the shearing strength, (2)from the numerical analysis, the maximum tensile stress occurred at opening nodes 1,7, these phenomena were agreed with the test results, (3)reinforcing method around openings have to carried out for stopping diagonal cracks, and (4)both, by steel plate, and wire mesh, are effective reinforcing methods.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 춘계학술발표회 논문집(I)
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• pp.378-381
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• 2006

Test results of four reinforced concrete two-span continuous deep beams are summarized. Main variables were the configuration of web opening reinforcement. Shear span-to-overall depth ratio and the size of the web opening were fixed by 1.0 and 0.5 a $\times$ 0.2 h, respectively. To control diagonal crack and enhance strength, it can be recommended that diagonal reinforcement crossing the crack plane joining between loading points and corner of openings should be provided.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 춘계학술대회 논문집
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• pp.559-571
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• 2007

Although the railroad industry has progressed in terms of amount and quality because of the opening of the new express ways in 2004 and the construction and openings of the express railroads of cities, the establishment of safety has been poor so there has been lurking accidents and it resulted in big accidents like a Daegu subway fire. Therefore, this study is to minimize damages of life and property by establishing GIS, a map for emergency and Activity-Action and emergency reaction scenario through a web in case of emergencies mentioned before.