• Title/Summary/Keyword: progressive failure

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Design of steel moment frames considering progressive collapse

  • Kim, Jinkoo;Park, Junhee
    • Steel and Composite Structures
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    • v.8 no.1
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    • pp.85-98
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    • 2008
  • In this study the progressive collapse potential of three- and nine-story special steel moment frames designed in accordance with current design code was evaluated by nonlinear static and dynamic analyses. It was observed that the model structures had high potential for progressive collapse when a first story column was suddenly removed. Then the size of beams required to satisfy the failure criteria for progressive collapse was obtained by the virtual work method; i.e., using the equilibrium of the external work done by gravity load due to loss of a column and the internal work done by plastic rotation of beams. According to the nonlinear dynamic analysis results, the model structures designed only for normal load turned out to have strong potential for progressive collapse whereas the structures designed by plastic design concept for progressive collapse satisfied the failure criterion recommended by the GSA guideline.

Evaluation of vierendeel peripheral frame as supporting structural element for prevention of progressive collapse

  • Khaloo, Alireza;Omidi, Hossein
    • Steel and Composite Structures
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    • v.26 no.5
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    • pp.549-556
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    • 2018
  • Progressive building collapse occurs when failure of a structural component leads to the failure and collapse of surrounding members, possibly promoting additional failure. Global system collapse will occur if the damaged system is unable to reach a new static equilibrium configuration. The most common type of primary failure which led to the progressive collapse phenomenon, is the sudden removal of a column by various factors. In this study, a method is proposed to prevent progressive collapse phenomena in structures subjected to removal of a single column. A vierendeel peripheral frame at roof level is used to redistribute the removed column's load on other columns of the structure. For analysis, quasi-static approach is used which considers various load combinations. This method, while economically affordable is easily applicable (also for new structures as well as for existing structures and without causing damage to their architectural requirements). Special emphasis is focused on the evolution of vertical displacements of column removal point. Even though additional stresses and displacements are experienced by removal of a structural load bearing column, the proposed method considerably reduces the displacement at the mentioned point and prevents the collapse of the structural frame.

Complex failure mechanism of rock slopes (암반 사면의 복합 파괴 메커니즘 규명)

  • Yoon, Woon-Sang;Jeong, Ui-Jin;Park, Sung-Wook;Choi, Jae-Won
    • Proceedings of the Korean Geotechical Society Conference
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    • 2006.10a
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    • pp.268-273
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    • 2006
  • Slope failures can be occurred by complex mechanism. In this cases, failures shows characteristics of complex failure mechanism during progressive mass movements. A case is a merged large slide with two sliding events triggered by slip on fault plane. Another case shows extension of failure area by sliding or subsidence at backyards of toppling areas. Generally, areas of progressive failures have wider than them of simple events.

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Progressive collapse resistance of low and mid-rise RC mercantile buildings subjected to a column failure

  • Demir, Aydin
    • Structural Engineering and Mechanics
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    • v.83 no.4
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    • pp.563-576
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    • 2022
  • This study aimed to evaluate the progressive collapse potential of buildings designed using conventional design codes for the merchant occupancy classification and subjected to a sudden column failure. For this purpose, three reinforced concrete buildings having different story numbers were designed according to the seismic design recommendations of TSCB-2019. Later on, the buildings were analyzed using the GSA-2016 and UFC 4-023-03 to observe their progressive collapse responses. Three columns were removed independently in the structures from different locations. Nonlinear dynamic analysis method for the alternate path direct design approach was implemented for the design evaluation. The plasticity of the structural members was simulated by using nonlinear fiber hinges. The moment, axial, and shear force interaction on the hinges was considered by the Modified Compression Field Theory. Moreover, an existing experimental study investigating the progressive collapse behavior of reinforced concrete structures was used to observe the validation of nonlinear fiber hinges and the applied analysis methodology. The study results deduce that a limited local collapse disproportionately more extensive than the initial failure was experienced on the buildings designed according to TSCB-2019. The mercantile structures designed according to current seismic codes require additional direct design considerations to improve their progressive collapse resistance against the risk of a sudden column loss.

Modeling of Progressive Failure in Concrete using Discontinuous Finite Elements (불연속 요소를 사용한 콘크리트 파괴진행의 유한요소 모델링)

  • Shim, Byul;Song, Ha-Won;Byun, Keun-Joo
    • Proceedings of the Korea Concrete Institute Conference
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    • 1996.04a
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    • pp.247-252
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    • 1996
  • In the concrete structures, cracks occur in various causes and the cracks seriously affect the functions of structures. The analysis techniques of progressive crack in the concrete have been improved with the advance of numerical techniques. The discrete crack model used in finite element program for the analysis of progressive failure is very effective, but it can not be easily implemented into numerical procedures because of difficult handing of nodal points in finite element meshes for crack growth. This paper introduces one of the techniques which skips the difficulty. In this paper, the modeling of progressive failure using finite element formulation is explained for the analysis of concrete fracture. The discontinuous element using the discontinuous shape function and the dual mapping technique in the numerical integration are implemented into finite element code for this purpose. It is shown that developed finite element program can predict the quasi-brittle behavior of concrete including ultimate load. The comparisons of the analysis results with other data are also shown.

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Modeling of progressive collapse of a multi-storey structure using a spring-mass-damper system

  • Yuan, Weifeng;Tan, Kang Hai
    • Structural Engineering and Mechanics
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    • v.37 no.1
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    • pp.79-93
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    • 2011
  • A simple mechanical model is proposed to demonstrate qualitatively the pancake progressive collapse of multi-storey structures. The impact between two collapsed storeys is simulated using a simple algorithm that builds on virtual mass-spring-damper system. To analyze various collapse modes, columns and beams are considered separately. Parametric studies show that the process of progressive collapse involves a large number of complex mechanisms. However, the proposed model provides a simple numerical tool to assess the overall behavior of collapse arising from a few initiating causes. Unique features, such as beam-to-beam connection failure criterion, and beam-to-column connection failure criterion are incorporated into the program. Besides, the criterion of local failure of structural members can also be easily incorporated into the proposed model.

Progressive collapse of reinforced concrete structures

  • Yagob, O.;Galal, K.;Naumoski, N.
    • Structural Engineering and Mechanics
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    • v.32 no.6
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    • pp.771-786
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    • 2009
  • In the past few decades, effects of natural hazards, such as earthquakes and wind, on existing structures have attracted the attention of researchers and designers. More recently, however, the phenomenon of progressive collapse is becoming more recognized in the field of structural engineering. In practice, the phenomenon can result from a number of abnormal loading events, such as bomb explosions, car bombs, accidental fires, accidental blast loadings, natural hazards, faulty design and construction practices, and premeditated terrorist acts. Progressive collapse can result not only in disproportionate structural failure, but also disproportionate loss of life and injuries. This paper provides an up-to-date comprehensive review of this phenomenon and its momentousness in structural engineering communities. The literature reveals that although the phenomenon of progressive collapse of buildings is receiving considerable attention in the professional engineering community, more research work is still needed in this field to develop a new methodology for efficient and inexpensive design to better protect buildings against progressive collapse.

Fatal progressive right heart failure in a pancreatic cancer patient

  • Byoun, Jeong Tae;Cho, Jae Young
    • Journal of Yeungnam Medical Science
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    • v.37 no.2
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    • pp.122-127
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    • 2020
  • Pulmonary tumor thrombotic microangiopathy (PTTM) is a rare but fatal complication of cancer and causes pulmonary hypertension and acute/subacute right heart failure. PTTM is most commonly associated with gastric cancer and more rarely associated with pancreatic cancer. We report a case of progressive right heart failure associated with clinically diagnosed pancreatic cancer, suggesting PTTM.

A controlled destruction and progressive collapse of 2D reinforced concrete frames

  • El houcine, Mourid;Said, Mamouri;Adnan, Ibrahimbegovic
    • Coupled systems mechanics
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    • v.7 no.2
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    • pp.111-139
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    • 2018
  • A successful methodology for modelling controlled destruction and progressive collapse of 2D reinforced concrete frames is presented in this paper. The strategy is subdivided into several aspects including the failure mechanism creation, and dynamic motion in failure represented with multibody system (MBS) simulation that are used to jointly capture controlled demolition. First phase employs linear elasto-plastic analysis with isotropic hardening along with softening plastic hinge concept to investigate the complete failure of structure, leading to creation of final failure mechanism that behaves like MBS. Second phase deals with simulation and control of the progressive collapse of the structure up to total demolition, using the nonlinear dynamic analysis, with conserving/decaying energy scheme which is performed on MBS. The contact between structure and ground is also considered in simulation of collapse process. The efficiency of the proposed methodology is proved with several numerical examples including six story reinforced concrete frame structures.

Analysis of Tunnel Behavior Using Progressive Rockmass Failure Technique (암반의 진행성 파괴 기법을 이용한 터널거동 분석)

  • 이성민;이윤규;신성렬
    • Tunnel and Underground Space
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    • v.9 no.4
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    • pp.288-295
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    • 1999
  • Concentrated stresses due to the underground tunnel excavation easily cause many problems such as yielding, popping, and failure at the immediate roof, wall and floor of tunnel. Therefore, it is very important to predict the possibility of these problems when a tunnel is excavated underground. There are two typical methods to predict these problems. The one is to predict problems from the analysis of field monitoring data and the other is to predict them from computer simulations using good site investment data. Using the second method, this study attempted to describe the time-dependent or progressive manner of immediate roof and wall due to the underground tunnel excavation. An iterative technique was used to represent progressive failure of rockmass with the Hoek and Brown theory. By developing and simulating three different shapes of twin tunnels, this research estimated the proper size of critical pillar width between tunnels, distributed stresses on the tunnel walls, and convergences of tunnel crowns. Moreover, results out of progressive failure technique based on the Hoek and Brown theory were compared with the results out of Mohr-Coulomb theory.

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