• 한국구조물진단유지관리공학회 논문집
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• 제9권1호
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• pp.233-241
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• 2005

본 연구는 콘크리트로 충전한 절곡된 단면을 갖는 각형강관 기둥의 부착특성을 매입인발(Pull-out) 시험을 통해 평가하였다. 시험체는 단면 $250{\times}250mm$의 강관 단면에 콘크리트를 충진한 PSSC기둥으로 표준형(P), 사다리꼴(I), 직사각형(II), 역사다리꼴(III)의 4가지 형태(Fig. 3)와, 부착길이에 대한 폭비 (L/D=2.0, 2.5, 3.0) 단면의 폭두깨비(d/t)으로 설정하여 총 13로 하였다. 실험결과 얇은 판요소 절곡된 강관과 콘크리트의 부착거동은 일반적인 부착거동과 유사하게 화학적 부착과 기계적 부착의 형태로 거동하였으며, 부착응력은 강판의 절곡형태가 (equation omitted)순으로 높게 나타났다. 또한 (equation omitted)타입 시험체의 경우에는 얇은 판요소를 갖는 단면임에도 불구하고 AIJ에서 제시하고 있는 $0.147N/mm^2$의 값을 상회하는 것으로 나타나 부착응력을 고려할 수 있을 것으로 판단되었다.

• Steel and Composite Structures
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• 제30권5호
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• pp.405-416
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• 2019

Profiled composite slab has been widely used in civil engineering due to its structural merits. The extension of this concept to the bearing wall forms the profiled composite wall, which consists of two external profiled steel plates and infill concrete. This paper investigates the structural behavior of this type of wall under axial compression. A series of compression tests on profiled composite walls consisting of varied types of profiled steel plate and edge confinement have been carried out. The test results are evaluated in terms of failure modes, load-axial displacement curves, strength index, ductility ratio, and load-strain response. It is found that the type of profiled steel plate has influence on the axial capacity and strength index, while edge confinement affects the failure mode and ductility. The test data are compared with the predictions by modern codes such as AISC 360, BS EN 1994-1-1, and CECS 159. It shows that BS EN 1994-1-1 and CECS 159 significantly overestimate the actual compressive capacity of profiled composite walls, while AISC 360 offers reasonable predictions. A method is then proposed, which takes into account the local buckling of profiled steel plates and the reduction in the concrete resistance due to profiling. The predictions show good correlation with the test results.

• Structural Engineering and Mechanics
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• 제21권4호
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• pp.407-422
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• 2005

Plate elements in fully profiled sandwich panels are generally subjected to local buckling failure modes and this behaviour is treated in design by using the conventional effective width method for plates with a width to thickness (b/t) ratio less than 100. If the plate elements are very slender (b/t > 1000), the panel failure is governed by wrinkling instead of local buckling and the strength is determined by the flexural wrinkling formula. The plate elements in fully profiled sandwich panels do not fail by wrinkling as their b/t ratio is generally in the range of 100 to 600. For this plate slenderness region, it was found that the current effective width formula overestimates the strength of the fully profiled sandwich panels whereas the wrinkling formula underestimates it. Hence a new effective width design equation has been developed for practical plate slenderness values. However, no guidelines exist to identify the plate slenderness (b/t) limits defining the local buckling, wrinkling and the intermediate regions so that appropriate design rules can be used based on plate slenderness ratios. A research study was therefore conducted using experimental and numerical studies to investigate the effect of plate slenderness ratio on the ultimate strength behaviour of foam supported steel plate elements. This paper presents the details of the study and the results.

• Steel and Composite Structures
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• 제42권1호
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• pp.33-48
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• 2022

This paper researches a lightweight composite structure referred to as the Profiled Steel Sheeting Dry Board (PSSDB). It is fundamentally produced by connecting a Profiled Steel Sheeting to Dry Board using mechanical screws. It is mainly employed as floor panels. However, almost all studies have focused on researching the one-way structural performance. Therefore, this study focuses on the bending behaviour of the two-way PSSDB floor system using both of Finite Element (FE) and Experimental analysis. Four panels were used in the experimental tests, and a mild steel plate has been applied at the bottom for two panels. For the FE process, models were created using ABAQUS software. 4 parametric studies have been utilized to understand the system's influential elements. From the experimental tests, it was found that using Steel Plate shall optimize the two-way action of the system and depending on the type of dry board the improvement in stiffness may reach up to 38%. It was shown from the FE analysis that the dry board, profiled steel sheeting and steel plat can affect the system by up to 10 %, 17% and 3% respectively, while applying a uniform load demonstrate a better two-way action.

• Structural Engineering and Mechanics
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• 제81권6호
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• pp.715-728
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• 2022

A new type of buckling-restrained braces (BRBs) with a longitudinally profiled steel plate working as the core (LPBRB) is proposed and experimentally investigated. Different from conventional BRBs with a constant thickness core, both stiffness and strength of the longitudinally profiled steel core along its longitudinal direction can change through itself variable thickness, thus the construction of LPBRB saves material and reduces the processing cost. Four full-scale component tests were conducted under quasi-static cyclic loading to evaluate the seismic performance of LPBRB. Three stiffening methods were used to improve the fatigue performance of LPBRBs, which were bolt-assembled T-shaped stiffening ribs, partly-welded stiffening ribs and stiffening segment without rib. The experimental results showed LPBRB specimens displayed stable hysteretic behavior and satisfactory seismic property. There was no instability or rupture until the axial ductility ratio achieved 11.0. Failure modes included the out-of-plane buckling of the stiffening part outside the restraining member and core plate fatigue fracture around the longitudinally profiled segment. The effect of the stiffening methods on the fatigue performance is discussed. The critical buckling load of longitudinally profiled segment is derived using Euler theory. The local bulging behavior of the outer steel tube is analyzed with an equivalent beam model. The design recommendations for LPBRB are presented finally.

• Steel and Composite Structures
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• 제31권1호
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• pp.1-12
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• 2019

Steel-concrete composite walls have been proposed and developed for applications in various types of structures. The double-skin profiled composite walls, as a natural development of composite flooring, provide structural and architectural merits. However, adequate intermediate fasteners between profiled steel plates and concrete core are required to fully mobilize the composite action and to improve the structural behavior of the wall. In this research, two new types of fasteners (i.e., threaded rods and vertical plates) were proposed and three specimens with different fastener types or fastener arrangements were tested under axial compression. The experimental results were evaluated in terms of failure modes, axial load versus axial displacement response, strength index, ductility index, and load-strain relationship. It was found that specimen with symmetrically arranged thread rods sustained more stable axial strain than that with staggered arranged threaded rods. Meanwhile, vertical plates are more suitable for practical use since they provide stronger confinement to profiled steel plate and effectively prevent the steel plate from early local buckling, which eventually enhance the composite action and increase the axial compressive capacity of the wall. The calculation methods were then proposed and good agreement was observed between the test results and the predicted results.

• 한국강구조학회 논문집
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• 제19권3호
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• pp.247-258
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• 2007

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.

• Steel and Composite Structures
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• 제34권1호
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• pp.91-105
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• 2020

Steel-concrete composite beam with profiled steel sheet has gained its popularity in the last two decades. Due to the ageing of these structures, retrofitting in terms of flexural strength is necessary to ensure that the aged structures can carry the increased traffic load throughout their design life. The steel ribs, which presented in the profiled steel deck, limit the use of shear connectors. This leads to a poor degree of composite action between the concrete slab and steel beam compared to the solid slab situation. As a result, the shear connectors that connects the slab and beam will be subjected to higher shear stress which may also require strengthening to increase the load carrying capacity of an existing composite structure. While most of the available studies focus on the strengthening of longitudinal shear and flexural strength separately, the present work investigates the effect of both flexural and longitudinal shear strengthening of steel-concrete composite beam with composite slab in terms of failure modes, ultimate load carrying capacity, ductility, end-slip, strain profile and interface differential strain. The flexural strengthening was conducted using carbon fibre reinforced polymer (CFRP) or steel plate on the soffit of the steel I-beam, while longitudinal shear capacity was enhanced using post-installed high strength bolts. Moreover, a combination of both the longitudinal shear and flexural strengthening techniques was also implemented (hybrid strengthening). It is concluded that hybrid strengthening improved the ultimate load carrying capacity and reduce slip and interface differential strain that lead to improved composite action. However, hybrid strengthening resulted in brittle failure mode that decreased ductility of the beam.

• Steel and Composite Structures
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• 제11권1호
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• pp.39-58
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• 2011

The subject of the ongoing research work is to analyze the composite action of the structural elements of composite slabs with profiled steel decking by experimental and numerical studies. The mechanical and frictional interlocks result in a complex behaviour and failure under horizontal shear action. This is why the design characteristics can be determined only by standardized experiments. The aim of the current research is to develop a computational method which can predict the behaviour of embossed mechanical bond under shear actions, in order to derive the design characteristics of composite slabs with profiled steel decking. In the first phase of the research a novel experimental analysis is completed on an individual concrete encased embossment of steel strip under shear action. The experimental behaviour modes and failure mechanisms are determined. In parallel with the tests a finite element model is developed to follow the ultimate behaviour of this type of embossment, assuming that the phenomenon is governed by the failure of the steel part. The model is verified and applied to analyse the effect of embossment's parameters on the behaviour. In the extended investigation different friction coefficients, plate thicknesses, heights and the size effects are studied. On the basis of the results the tendencies of the ultimate behaviour and resistance by the studied embossment's characteristics are concluded.

• 한국공간구조학회논문집
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• 제7권5호
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• pp.39-48
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• 2007

최근, 구조물의 건설에서 경제적으로 개선된 구조시스템을 개발하는데 많은 역량이 집중되고 있다. 이에 따라, 구조물을 단순화시키고 시공기간을 단축시키고자 고성능강의 사용이 증가되고 있다. 구조물에 가해지는 단면적을 효과적으로 분배시키고, 자중감소와 용접개소를 줄일 수 있는 이점 등으로 인하여, 구조요소로서 LP강판에 대한 관심이 늘고 있다. 이러한 LP강판은 유럽에서 개발되어, 한국에서도 강구조물에 급속도로 사용이 증가되고 있으나, 이에 대한 구조적인 적용검토에 대한 연구는 아직 미흡한 상태이다. 본 연구에서는 유한요소해석의 고체요소을 이용하여 여러 단면형상에 대한 단면력과 처짐을 검토하여, 국내 생산 가능한 LP강판 제품에 대한 작업성, 효율성 및 경제성을 확인하였다.