Security Risk Evaluation on Long Span Bridge Structure Based on Grey Fuzzy Theory

In order to evaluate security risks of long span bridge structure more scientifically and accurately. According to the principles of scientific, integrity, this paper applies grey-fuzzy theory to divide the security risk factors of long span bridge structure into quality cable, tower concrete foundations, weld cracks, expansion joints, and bridge deck pavement condition five types. First, according to the evaluation rules, use expert scoring method to score the individual evaluation index of long span bridge structure, fraction is in 0~100.Analyze the expert scoring by using grey theory, substitute the score into albino function, calculate grey statistics, and form weight matrix. This method can be used for comprehensive evaluation of security risks assessment of long span bridge structure.

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Fire of steel and composite beam bridges

IABSE Congress, New York, New York 2019: The Evolving Metropolis ◽

10.2749/newyork.2019.0724 ◽

2019 ◽

Author(s):

Henryk Zobel ◽

Wojciech Karwowski ◽

Agnieszka Golubińska ◽

Thakaa Al-Khafaji

Keyword(s):

Fire Resistance ◽

Composite Beam ◽

Structural Integrity ◽

Bridge Structure ◽

Long Span ◽

Long Span Bridge ◽

Bridge Structures ◽

Fire Scenarios ◽

Design Construction ◽

Cable Stayed Bridges

<p>The problem of bridge fires is growing. Because of a bad experience in Poland, it was decided to improve fire resistance of long span bridge structures, and of cable-stayed bridges in particular. Statistics shows that fire is a real threat to this kind of structure. They also confirm that the worst results of fire are for those with an orthotropic deck rather than with a concrete one. The basic problems to solve are how to predict fire resistance of a particular bridge and how to ensure safety and structural integrity of the bridge structure. Taking into account the fact that bridge standards do not include information relating to fire protection, and fire standards do not determine rules for design, construction and maintenance of such structures, there are no regulations for this problem. Fire scenarios are devoted to buildings, but the thermo-structural behavior of bridges is different.</p>

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Static and Dynamic Response Contrast Simulation of Long-Span Beam Bridge Subjected to Flowing Ice

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.594-597.1573 ◽

2012 ◽

Vol 594-597 ◽

pp. 1573-1576

Author(s):

Zhi Ping Bai ◽

Xie Dong Zhang ◽

Cheng Lin Han

Keyword(s):

Finite Element Method ◽

Yellow River ◽

Bridge Structure ◽

Deformation Effect ◽

Soil Function ◽

Action Mode ◽

Long Span ◽

Long Span Bridge ◽

Static Action ◽

Beam Bridge

According to pile-soil function and damper boundary condition influence by Finite Element Method, taking Bao-Shu yellow river extra long-span bridge as the project object, the deformation effect of the bridge subjected to flowing and melting ice in spring was analyzed considering static and dynamical action mode. The results revealed that the deformation from this kind of action is tittly small and the bridge structure is reliable and stable. Also the deformation effect of the pier from dynamic ice action is larger than static action. While for two or more piers, the results are reverse.Then the calculation and analysis have been put into design and construction stage.

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Method of Damage Evaluation of Long-Span Arch Bridge Subjected to Blast Loading

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.178-181.2405 ◽

2012 ◽

Vol 178-181 ◽

pp. 2405-2411

Author(s):

Li He ◽

Yong Jiu Qian

Keyword(s):

Evaluation Method ◽

Comprehensive Evaluation ◽

Fuzzy Theory ◽

Highway Bridges ◽

Fuzzy Comprehensive Evaluation ◽

Technical Condition ◽

Damage Evaluation ◽

Arch Bridge ◽

Long Span ◽

Arch Bridges

A variety of conventional weapons equipped with explosive are used to destroy the significant long-span arch bridge. Because of the special function of the weapons and the complexity of the arch bridge, the damage results with the features of uncertainty and fuzzy are assessed with fuzzy theory. Combined with the standards for technical condition evaluation of highway bridges and wartime specific requirements, the fuzzy mathematical model based on the fuzzy mathematics theory and method is established to judgment comprehensively the arch technical condition. The hirarchy fuzzy comprehensive evaluation method is applied to determine the technical state grade of the damaged arch bridge. The method of damage evaluation provides the effective reference for the emergency repairmen of the arch bridges.

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Random Seismic Response Analysis of Long-Span Bridge Structures

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.204-208.2157 ◽

2012 ◽

Vol 204-208 ◽

pp. 2157-2161 ◽

Cited By ~ 1

Author(s):

Zhang Jun Liu ◽

Yan Fu Xing ◽

Yong Wan

Keyword(s):

Seismic Response ◽

Independent Random Variables ◽

Response Analysis ◽

Orthogonal Expansion ◽

Bridge Structure ◽

Seismic Response Analysis ◽

Long Span ◽

Long Span Bridge ◽

Bridge Structures ◽

Random Seismic Response

Based on the orthogonal expansion method of stochastic processes, seismic acceleration processes can be represented as a linear combination of deterministic functions modulated by a set of mutually independent random variables. In conjunction with the probability density evolution method, the random seismic response of bridge structures can be successfully researched. A long-span bridge structure is taken as an example. The probabilistic information of the response of a long-span bridge structure in different control under earthquake excitations is investigated. The investigation provides a new approach to the random seismic response analysis of long-span bridge structures.

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