• Steel and Composite Structures
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• 제32권3호
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• pp.347-359
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• 2019

Modular construction has been increasingly used for mid-to-high rise buildings attributable to the high construction speed, improved quality and low environmental pollution. The individual and repetitive room-sized module unit is usually fully finished in the factory and installed on-site to constitute an integrated construction. However, there is a lack of design guidance on modular structures. This paper mainly focuses on the evaluation of the initial stiffness of corrugated steel plate shears walls (CSPSWs) in container-like modular construction. A finite element model was firstly developed and verified against the existing cyclic tests. The theoretical formulas predicting the initial stiffness of CSPSWs were then derived. The accuracy of the theoretical formulas was verified by the related numerical and test results. Furthermore, parametric analysis was conducted and the influence of the geometrical parameters on the initial stiffness of CSPSWs was discussed and evaluated in detail. The present study provides practical design formulas and recommendations for CSPSWs in modular construction, which are useful to broaden the application of modular construction in high-rise buildings and seismic area.

• Computers and Concrete
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• 제5권2호
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• pp.135-154
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• 2008

This paper presents a nonlinear finite element analysis procedure for the seismic performance assessment of reinforced concrete bridge piers with unbonded reinforcing or prestressing bars. A computer program named RCAHEST (Reinforced Concrete Analysis in Higher Evaluation System Technology) is used to analyze reinforced concrete structures; this program was also used in our study. Tensile, compressive and shear models of cracked concrete and models of reinforcing and prestressing steel were used account for material nonlinearity of reinforced concrete. The smeared crack approach was incorporated. To represent the interaction between unbonded reinforcing or prestressing bar and concrete, an unbonded reinforcing or prestressing bar element based on the finite element method was developed in this study. The proposed numerical method for the seismic performance assessment of reinforced concrete bridge piers with unbonded reinforcing or prestressing bars is verified by comparison of its results with reliable experimental results.

• Journal of Mechanical Science and Technology
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• 제15권11호
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• pp.1499-1506
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• 2001

Various transition elements are used in general for the effective finite element analysis of complicated mechanical structures. In this paper, a solid-to-beam transition finite element, which can b e used for connecting a C1-continuity beam element to a continuum solid element, is proposed. The shape functions of the transition finite element are derived to meet the compatibility condition, and a transition element equation is formulated by the conventional finite element procedure. In order to show the effectiveness and convergence characteristics of the proposed transition element, numerical tests are performed for various examples. As a result of this study, following conclusions are obtained. (1) The proposed transition element, which meets the compatibility of the primary variables, exhibits excellent accuracy. (2) In case of using the proposed transition element, the number of nodes in the finite element model may be considerably reduced and the model construction becomes more convenient. (3) This formulation method can be applied to the usage of higher order elements.

• 한국건설관리학회논문집
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• 제6권6호
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• pp.142-151
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• 2005

공공 건설공사에 있어서 발주관청에서 산정한 예정공사기간과 실제 공사기간 사이에 차이가 발생하여 당초 계획했던 프로젝트가 예정준공일보다 지연되는 경우가 빈번하게 발생한다. 이는 공사지연에 따른 시공 중 문제점뿐만 아니라 시설물사용 계획의 차질로 초래되는 물류비용증가, 시민불편가중, 시설물을 이용한 생산 및 공급차질과 이로 인한 각 분야의 막대한 손실 등으로 이어진다. 이러한 손실들을 줄이기 위해서는 발주시 산정하는 예정공사기간의 정확도를 높여야 한다. 본 연구는 발주관청의 예정공사기간 산정시 지표로 활용할 수 있는 공사기간보정요소를 포함하는 예정공사기간 산정모델을 제시하여 적정공사기간을 확보함으로서 시공 중의 공기 연장 빈도를 줄이고 나아가서는 공공 프로젝트의 성공적인 운영에 기여하고자 한다.

• 한국강구조학회 논문집
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• 제13권6호
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• pp.715-723
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• 2001

이 논문은 T-스티프너보강된 GFT기둥-H형강보 실대형 접합부의 거동을 나타낸다. 수직요소와 수평요소로 구성된 6개 실험체의 T-스트프너는 보의 전소성모멘트에 대한 강도비를 주요변수로 하여 제작되었다. 실험을 통하여 얻은 주요 내용은 강도, 강성과 소성회전능력이다. 모든 실험체는 대체로 안정된 이력거동을 나타내었으며, 특히 수평요소는 수직요소보다 강도와 강성에 더욱더 큰 영향을 준다. 보의 소성회전성능에 있어서, 조기에 파단한 TS-2를 제외한 실험체들의 평균 보소성회전각은 2.97% rad.이다.

• Structural Engineering and Mechanics
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• 제36권2호
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• pp.207-223
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• 2010

The aim of this study concerns with the construction stage analysis of highway bridges constructed with balanced cantilever method using time dependent material properties. K$\ddot{o}$m$\ddot{u}$rhan Highway Bridge constructed with balanced cantilever method and located on the 51st km of Elazi$\check{g}$-Malatya, Turkey, highway over Firat River is selected as an application. Finite element models of the bridge are modelled using SAP2000 program. Geometric nonlinearity is taken into consideration in the analysis using P-Delta plus large displacement criterion. The time dependent material strength variations and geometric variations are included in the analysis. Elasticity modulus, creep and shrinkage are computed for different stages of the construction process. The structural behaviour of the bridge at different construction stages has been examined. Two different finite element analyses with and without construction stages are carried out and results are compared with each other. As analyses result, variation of internal forces such as bending moment, axial forces and shear forces for bridge deck and column are given with detail. It is seen that construction stage analysis has remarkable effect on the structural behaviour of the bridge.

• Structural Engineering and Mechanics
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• 제19권2호
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• pp.173-184
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• 2005

For reducing construction cost, two-plate-girder bridges are getting popular in Japan. This type of bridge employs a PC slab, which is often cast-in-place. In such a case, concrete is not usually cast over the whole slab at one time: some portions are constructed earlier than the rest. Therefore, a construction joint is inevitably created. Due to the drying shrinkage of concrete, tension stress may occur in concrete slab. High tensile stress can be expected near the construction joint where concretes with different ages meet. Moreover, prestressing is not applied over the whole length of slab at one time. This may also serve as a source of tensile stress in the slab. Thus there is a chance that cast-in-place PC slab, especially near the construction joint, may be subjected to tensile cracking. In the present study, stress states near the construction joint in the cast-in-place PC slab of a two-plate-girder bridge are investigated numerically. The finite element method is employed and the three-dimensional analysis is conducted to see the influence of dry shrinkage and prestressing. The stress states in the PC slab thus obtained are discussed. The simplified model of a plate girder for this class of analysis is also proposed.

• Computers and Concrete
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• 제10권6호
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• pp.663-681
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• 2012

This paper presents a parametric study of the plastic hinge length of circular reinforced concrete columns using a three-dimensional finite element analysis method, and using the Taguchi robust design method to reduce computational cost. Parameters examined include the longitudinal reinforcing ratio, the shear span-to-depth ratio, the axial force ratio and the concrete compressive strength. The study considers longitudinal reinforcement with yield strengths of 414 MPa and 685 MPa, and proposes simplified formulas for the plastic hinge length of circular reinforced concrete columns, showing that increases in plastic hinge length correlate to increases in the axial load, longitudinal reinforcing and shear span-to-depth ratios. As concrete strength increases, the plastic hinge length decreases for the 414 MPa case but increases for the 685 MPa case.

• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2007년도 추계학술발표논문집
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• pp.375-377
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• 2007

The purpose of this study was to investigate total $CO_2$ amount of steel and reinforced concrete construction, and compare and analyze $CO_2$ amount on construction-material. And then it was studied about new element that environment compatibility of architecture structure design based on paradigm of environment age. Architecture action should have proceeded course that reduce burden of the earth environment in relation between architecture and environment and increase contact of human and nature. As environment compatibility development is emphasized with architecture development, architecture structure design give improvement of one important element that environment compatibility except stability, function, economy and necessary propriety of environment compatability of construction design.

• Coupled systems mechanics
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• 제11권5호
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• pp.439-458
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• 2022

Over-coating is one of the most popular engineering practices to strengthen Reinforced Concrete (RC) structures, due to the relative quickness and ease of construction. It consists of an external coat bonded to the outer surface of the structural RC element, either by the use of chemical adhesives, mechanical anchor bolts or simply mortar injection. In contrast to these constructive advantages, the numerical estimation of the bearing capacity of the strengthened reinforced concrete element is still complicated, not only for the complexity of modelling a flexible membrane or plate attached to a quasi-rigid solid, but also for the difficulties that raise of simulating any potential delamination between both materials. For these reasons, the standard engineering calculations used in the practice remain very approximated and clumsy. In this work, we propose the formulation of a new 2D solid-layer finite element capable to link a solid body with a flexible thin layer, as it were the "skin" of the body, allowing the potential delamination between both materials. In numerical terms, this "skin" element is intended to work as a transitional region between a solid body (modelled with a classical formulation of a standard quadrilateral four-nodes element) and a flexible coat layer (modelled with cubic beam element), dealing with the incompatibility of Degrees-Of-Freedom between them (two DOF for the solid and three DOF for the beam). The aim of the solid-layer element is to simplify the mesh construction of the strengthened RC element being aware of two aspects: a) to prevent the inappropriate use of very small solid elements to simulate the coat; b) to improve the numerical estimation of the real bearing capacity of the strengthened element when the coat is attached or detached from the solid body.