Updating Fatigue Damage Coefficient in Railway Bridge Design Code in China

A bridge is nowadays more than a structure that connects people over an obstacle. When a bridge has to be built in an urban area, either it has to be a landmark or it should blend away in the environment. The use of curved steel panels is one option to obtain these requirements. However, due to a lack of knowledge, engineers end up with a conservative design to implement these structural elements. For that reason, a Finite Element Model is made of a railway bridge, where the outer webs of the main girders have a varying web curvature. Six different models are made and compared. The most important parameters that are compared are the deformations and the stresses in the webs. The study finds that curved webs have an equal or even better behavior than flat webs, even with smaller web thickness. This makes that designers can use curved webs in their design, without needing extra steel to make their design safe.

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Canadian Bridge Design Code Provisions for Fiber-Reinforced Structures

Journal of Composites for Construction ◽

10.1061/(asce)1090-0268(2000)4:1(3) ◽

2000 ◽

Vol 4 (1) ◽

pp. 3-15 ◽

Cited By ~ 29

Author(s):

Baidar Bakht ◽

George Al-Bazi ◽

Nemy Banthia ◽

Moe Cheung ◽

Marie-Anne Erki ◽

...

Keyword(s):

Fiber Reinforced ◽

Design Code ◽

Bridge Design ◽

Code Provisions

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Equivalent area of voided slabs

Canadian Journal of Civil Engineering ◽

10.1139/l98-002 ◽

1998 ◽

Vol 25 (4) ◽

pp. 797-801 ◽

Cited By ~ 1

Author(s):

Leslie G Jaeger ◽

Baidar Bakht ◽

Gamil Tadros

Keyword(s):

Simple Expression ◽

Technical Note ◽

Axial Stiffness ◽

Highway Bridge ◽

Slab Thickness ◽

Design Code ◽

Bridge Design ◽

Equivalent Thickness ◽

Simple Alternative ◽

Equivalent Area

In order to calculate prestress losses in the transverse prestressing of voided concrete slabs, it is sometimes convenient to estimate the thickness of an equivalent solid slab. The Ontario Highway Bridge Design Code, as well as the forthcoming Canadian Highway Bridge Design Code, specifies a simple expression for calculating this equivalent thickness. This expression is reviewed in this technical note, and a simple alternative expression, believed to be more accurate, is proposed, along with its derivation. It is shown that the equivalent solid slab thickness obtained from consideration of in-plane forces is also applicable to transverse shear deformations, provided that the usual approximations of elementary strength of materials are used in both cases.Key words: axial stiffness, equivalent area, shear deformation, transverse prestressing, voided slab, slab.

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Reliability-based design criteria for timber bridges in Ontario

Canadian Journal of Civil Engineering ◽

10.1139/l86-001 ◽

1986 ◽

Vol 13 (1) ◽

pp. 1-7 ◽

Cited By ~ 3

Author(s):

Andrzej S. Nowak ◽

Raymond J. Taylor

Keyword(s):

Reliability Index ◽

Structural Reliability ◽

Structural Safety ◽

Design Code ◽

Bridge Design ◽

Limit States ◽

Acceptance Criterion ◽

Reliability Based Design ◽

Load And Resistance Factor ◽

Timber Bridges

The new Ontario Highway Bridge Design Code (OHBDC) is based on limit states theory and therefore uses a load and resistance factor format. This paper deals with the development of the basis for the timber bridge design provisions (OHBDC). Three structural systems are considered: sawn timber stringers, laminated nailed decks, and prestressed laminated decks. The latter system has been successfully used in Ontario for the last 7 years.The acceptance criterion in calculation of load and resistance factors is structural reliability. It is required that bridges designed using the new code must have a reliability equal to or greater than a preselected target value. Reliability is measured in terms of the reliability index. The safety analysis is performed for a structural system rather than for individual members. The live load model was developed on the basis of available truck survey data. Material properties are based on extensive in-grade test results. Numerical examples are included to demonstrate the presented approach. Key words: bridge deck, design code, prestressed timber, reliability, reliability index, stringers, structural safety, timber bridges.

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