Some Recent Studies on Plastic Behavior of Plates Subjected to Large Impact Loads

2002 ◽  
Vol 124 (3) ◽  
pp. 125-131 ◽  
Author(s):  
Ge Wang
Keyword(s):  
Steel Plates ◽  
Large Impact ◽  
Plastic Behavior ◽  
Complex Object ◽  
Impact Loads ◽  
Complex Interactions ◽  
Analytical Formulas ◽  
Membrane Stretching ◽  
The Many ◽  
Deformation Patterns

This paper reviews some recent studies on the plastic behavior of steel plates subjected to large impact loads. This is an important topic for risk assessments and safety evaluations because of the ever heightened public concern about safety of marine structures and potential harm to the environment due to marine accidents. Emphasis is given to the complex plastic deformation patterns recently identified, including plate punching, plate tearing, and local denting of web girders. Descriptions are given of the complex interactions of the many mechanisms involved in these deformation patterns, including membrane stretching, local plastic bending, complex object geometry, rupture, cracking and friction. Advanced analytical formulas that can be used to describe these behavior mechanisms are introduced. These formulas are based on the advanced structural crashworthiness methodology.

Recent Studies on the Dynamic Plastic Behavior of Structures

1989 ◽  
Vol 42 (4) ◽  
pp. 95-115 ◽  
Author(s):  
Norman Jones
Keyword(s):  
Brittle Fracture ◽  
Dynamic Loads ◽  
Large Impact ◽  
Plastic Behavior ◽  
Impact Loads ◽  
Plastic Strains ◽  
Review Of The Literature ◽  
Rigid Plastic ◽  
Plastic Buckling ◽  
Fracture Transition

This article contains a review of the literature, which has been published recently, on the dynamic plastic behavior of simple structures. The dynamic loads cause large plastic strains which dominate material elastic effects. Thus, the accuracy of various refinements of simple rigid-plastic methods are discussed, together with the phenomena of pseudoshakedown under repeated loads, dynamic plastic buckling, and dynamic progressive buckling. Recent studies are also reported on similitude under large impact loads, and on the ductile-brittle fracture transition due to the changes in the physical dimensions of a structure.

scholarly journals Māori Urban Migrations and Identities, ‘Ko Ngā Iwi Nuku Whenua’: A study of Urbanisation in the Wellington Region during the Twentieth Century

2021 ◽  
Author(s):  
◽  
Erin Keenan
Keyword(s):  
Twentieth Century ◽  
Urban Areas ◽  
Urban Migration ◽  
World War ◽  
Historical Sources ◽  
The Past ◽  
Complex Interactions ◽  
The Subject ◽  
The Many ◽  
Migration Experiences

<p>Māori urbanisation and urban migrations have been the subject of much discussion and research, especially following World War Two when Māori individuals, whānau and communities increasingly became residents of towns and cities that were overwhelmingly Pākehā populated. However, Māori urbanisation experiences and urban migrations are difficult topics to address because kaumātua are reluctant to discuss ‘urban Māori’, especially considering its implications for Māori identities. The original contribution this thesis makes to histories of Māori urban migrations is that it explores these and other understandings of urbanisations to discover some of their historical influences. By discussing urbanisations directly with kaumātua and exploring historical sources of Māori living in, and moving to, the urban spaces of Wellington and the Hutt Valley through the twentieth century, this thesis is a ‘meeting place’ for a range of perspectives on the meanings of urbanisations from the past and the present. Although urbanisation was an incredible time of material change for the individuals and whānau who chose to move into cities such as Wellington, the histories of urban migration experiences exist within a scope of Māori and iwi worldviews that gave rise to multiple experiences and understandings of urbanisations. The Wellington region is used to show that Māori in towns and cities used Māori social and cultural forms in urban areas so that they could, through the many challenges of becoming urban-dwelling, ensure the persistence of their Māoritanga. Urbanisations also allowed Māori to both use traditional identities in urban areas, as well as develop new relationships modelled on kinship. The Ngāti Pōneke community is used as an example of the complex interactions between these identities and how many Māori became active residents in but not conceptually ‘of’ cities. As a result, the multiple and layered Māori identities that permeate throughout Māori experiences of the present and the past are important considerations in approaching and discussing urbanisations. Urban Māori communities have emphasised the significance of varied and layered Māori identities, and this became particularly pronounced through the Māori urban migrations of the twentieth century.</p>

scholarly journals Characterisation of the Semliki Forest Virus-host cell interactome reveals the viral capsid protein as an inhibitor of nonsense-mediated mRNA decay

2020 ◽  
Author(s):  
Lara Contu ◽  
Giuseppe Balistreri ◽  
Michal Domanski ◽  
Anne-Christine Uldry ◽  
Oliver Mühlemann
Keyword(s):  
Host Cell ◽  
Capsid Protein ◽  
Mrna Decay ◽  
Semliki Forest Virus ◽  
Protein Protein Interaction ◽  
Host Cell Proteins ◽  
Complex Interactions ◽  
Nonsense Mediated Mrna Decay ◽  
Interaction Map ◽  
The Many

AbstractThe positive-sense, single-stranded RNA alphaviruses pose a potential epidemic threat. Understanding the complex interactions between the viral and the host cell proteins is crucial for elucidating the mechanisms underlying successful virus replication strategies and for developing specific antiviral interventions. Here we present the first comprehensive protein-protein interaction map between the proteins of Semliki Forest Virus (SFV), a mosquito-borne member of the alphaviruses, and host cell proteins. Among the many identified cellular interactors of SFV proteins, the enrichment of factors involved in translation and nonsense-mediated mRNA decay (NMD) was striking, reflecting the virus’ hijacking of the translation machinery and indicating viral countermeasures for escaping NMD by inhibiting NMD at later time points during the infectious cycle. In addition to observing a general inhibition of NMD about 4 hours post infection, we also demonstrate that transient expression of the SFV capsid protein is sufficient to inhibit NMD in cells, suggesting that the massive production of capsid protein during the SFV reproduction cycle is responsible for NMD inhibition.

INFLUENCE OF RECTANGULAR STEEL SPLICE-SLEEVE FOR PRECAST CONCRETE CONNECTION

2015 ◽  
Vol 77 (12) ◽  
Author(s):  
Ahmad Baharuddin Abd Rahman ◽  
Tan Kee Hong ◽  
Izni Syahrizal Ibrahim ◽  
Roslli Noor Mohamed
Keyword(s):  
Structural Integrity ◽  
Precast Concrete ◽  
Tensile Load ◽  
Steel Plates ◽  
Steel Bar ◽  
Tensile Performance ◽  
Bond Property ◽  
The Many ◽  
Steel Sleeve

Precast concrete building system has gained its popularity in Malaysia because of the many advantages such as high quality of structural components, less labour intensive at the construction site, and shorter completion time of a project. One of the constraints in precast concrete structures is to ensure that the connections are strong enough to ensure the structural integrity and robustness of the overall frames. In this study, a total of nine rectangular steel splice-sleeve connections were tested experimentally under incremental tensile loads. Two steel plates were inserted and welded to each end of the steel splice-sleeve. The steel plates act as shear key to provide the interlocking mechanism to the grout and to enhance the bond property between the grout and the splice. These plates were adopted to prevent the grout slippage from the sleeve. The grout strength, embedded steel bar lengths and the size of the steel sleeve splice were varied among the specimens to study their effect on the tensile performance of the connection. The results showed that the higher strength of grout, longer embedded length of steel bar and smaller size of the sleeve contributes to a higher ultimate tensile load.

On the Mechanics of Micro-Thin Foil Production

1973 ◽  
Vol 95 (3) ◽  
pp. 803-808 ◽  
Author(s):  
E. G. Thomsen ◽  
H. H. Thomsen
Keyword(s):  
Thin Foil ◽  
Large Impact ◽  
Interfacial Friction ◽  
Impact Loads ◽  
Metal Foil ◽  
Poisson Effect ◽  
Compression Process ◽  
Leaf Production ◽  
Actual Mechanism ◽  
Stretching Process

The mechanics of micro-thin foil or leaf production by hammering has been analyzed. It was found that the metal foil cannot be reduced by a compression process alone because of the large impact loads that would be required, due to interfacial friction between the foil and the separating paper sheets. It is demonstrated that a likely mechanism is a plastic stretching process of the metal combined with relatively large elastic stretching of the paper due to the Poisson effect when a blow is struck. The actual mechanism is probably a combination of stretching and slipping of the metal.

A Direct Design Procedure for FPSO Side Structures Against Large Impact Loads

2009 ◽  
Vol 131 (3) ◽  
Author(s):  
Lin Hong ◽  
Jørgen Amdahl ◽  
Ge Wang
Keyword(s):  
Heavy Traffic ◽  
Limit State ◽  
Design Procedure ◽  
Large Impact ◽  
Collapse Mechanism ◽  
Impact Loads ◽  
Element Analysis ◽  
Direct Design ◽  
Offshore Industry ◽  
The Impact

The performance and consequence of FPSOs subjected to large impact loads such as collisions from supply vessels or merchant vessels are of great concern in the offshore industry, notably when they are located close to heavy traffic lanes. Due to the lack of operation experience for ship-shaped FPSOs, direct design procedures are needed to rationalize the structural design of FPSOs, which can mitigate the consequence of collision accident and avoid possible contaminated compartment flooding. In this paper, three collision scenarios between a FPSO and a bulbous supply vessel are analyzed through explicit nonlinear finite element analysis code LS-DYNA. Thereafter, a direct design procedure is proposed for ship-shaped FPSO side structure against accidental collision forces, which follows the principle of accidental limit state. The procedure comprises the determination of the impact forces, shell plating, and stiffener framing design, and the consideration of the acceptance criterion. The proposed method is especially useful in the preliminary design phase because the design procedure for plating and stiffener is based on analytical formulas derived from plastic method and appropriate collapse mechanism. The side structure decided by the proposed design procedure also complies with the strength design principle that has been adopted in NORSOK standard. The proposed approach is demonstrated by the design of the FPSO side structure against impact loads from a 7500 tons supply vessel and verified by means of integrated collision analysis. The procedure could also be served to estimate the damage due to accidental loads.

Test of Thick Rubber Bearings on its Compressive Properties

2014 ◽  
Vol 919-921 ◽  
pp. 348-354 ◽  
Author(s):  
Hao Wen Chen ◽  
Peng Pan ◽  
Jun Cai Liu ◽  
Yu Sakurai ◽  
Masahiro Nakamura ◽  
...  
Keyword(s):  
Vibration Control ◽  
Steel Plates ◽  
Temperature Dependency ◽  
Test Results ◽  
Compressive Properties ◽  
Frequency Dependency ◽  
Current Design ◽  
High Damping Rubber ◽  
The Many ◽  
Rubber Bearings

Vibration is an important comfort issue for the metro surrounding buildings. Among the many methods of subway vibration control, building isolation is the necessary supplement to the track isolation for metro surrounding buildings with sensitive constructive forms or specific comfort needs. Laminated rubber bearings are widely used for the building isolation. In order to further improve the isolation effectiveness, researchers intend to use laminated rubber bearings with relatively thick rubber layers. However, the frequency dependency and temperature dependency are not well explored for the thick rubber bearings. And since constrains from the steel plates to rubber layers are relatively small for thick rubber bearings, its not clear if it is accurate to simply apply the equations for common laminated rubber bearings to the thick ones. In this paper, a compressive properties test is carried out for both thick and thin rubber bearings. Both thick and thin rubber bearings are manufactured by a kind of High Damping Rubber (HDR) and a kind of Nature Rubber (NR). The frequency dependency and temperature dependency are tested. The accuracy of applying the current design equations to thick rubber bearings is discussed based on the test results.

scholarly journals British Experience on Democratic Interaction between Power and Opposition

2017 ◽  
pp. 63-80
Author(s):  
N. Yakovenko
Keyword(s):  
Common Good ◽  
Modern Society ◽  
Power Structures ◽  
Progressive Development ◽  
Complex Interactions ◽  
Political Forces ◽  
Stable Vision ◽  
British Experience ◽  
The Many ◽  
The Uk

The article deals with complex interactions of main political forces inside the British Parliament, activities of Her Majesty’s Opposition in different periods of historical development of Great Britain. Constructive competition between Opposition and the ruling party is stressed as a phenomenon causing progressive development of the United Kingdom and coming to proper decisions concerning its further democratic course. Both power and Opposition are mentioned to be united by the same purpose which is flourishing and common good of their state, welfare of their citizens and stable vision of the future. Relations between power and Opposition are always complex, multidimensional and sensitive to any changes in the political era. Significant influence on the nature of their relationship is made through the transformation taking place in modern society and its scientific perception. In the UK it is the active Opposition provides dynamism and fruitfulness, so that parliamentary government has the ability to predict future horizons of its reign. Studying the many-sided British experience in the labyrinth of power seems to be extremely significant for Ukraine considering its complicated apprehension of contradictory interaction and between power structures and other political forces facing contemporary challenges.

A Recommended Method for SC Wall Design-Evaluation Regarding the Elasto-Plastic Behavior Under Beyond Design Basis Seismic Loading

2018 ◽  
Author(s):  
Ziduan Shang ◽  
Xiao Huang ◽  
Yugang Sun ◽  
Meng Chu
Keyword(s):  
Nuclear Power ◽  
Power Plants ◽  
Constitutive Relations ◽  
Steel Plates ◽  
Plastic State ◽  
Plastic Behavior ◽  
Analytical Methodology ◽  
Composite State ◽  
Composite Function ◽  
Design Basis

Steel Concrete Composite Wall (SC-Wall) is a unique composite structural component designed and used for shield building wall in new nuclear power plants construction. The composite function (action) of steel-plate and concrete is through the use of embedded studs, which are designed in an appropriate pattern to secure the connections between concrete and surface steel-plates. Thus the behavior of studs (primarily shear behavior) determines the composite state and its functions for serving as an integrated one-piece (or monolithic) section. For elastic state (linear) and ultimate state design, ACI 318 / 349 and recent published design specifications provide formula / equations for shear design-evaluations between plate stud and concrete; but for Beyond Design Basis (BDB) loading conditions, since the section behaves in elasto-plastic (or plastic) state, the constitutive relations among plate-stud-concrete have not yet established in current prevailing codes / or standards. Considering this situation, this paper is contributed to investigate the section behaviors of SC wall subjected to above BDB seismic loadings, provide recommendations for constitutive relations to reveal the actual strain-stress conditions and composite states, and further provide criteria suitable for section design and evaluations under such a circumstance. This research and investigation are based on an analytical methodology and physical model.

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