Review of Steel ratio Specifications in Korean Highway Bridge Design Code (Limit States Design) for the Design of RC Flexural Members

Canada has two national civil codes of practice that include geotechnical design provisions: the National Building Code of Canada and the Canadian Highway Bridge Design Code. For structural designs, both of these codes have been employing a load and resistance factor format embedded within a limit states design framework since the mid-1970s. Unfortunately, limit states design in geotechnical engineering has been lagging well behind that in structural engineering for the simple fact that the ground is by far the most variable (and hence uncertain) of engineering materials. Although the first implementation of a geotechnical limit states design code appeared in Denmark in 1956, it was not until 1979 that the concept began to appear in Canadian design codes, i.e., in the Ontario Highway Bridge Design Code, which later became the Canadian Highway Bridge Design Code (CHBDC). The geotechnical design provisions in the CHBDC have evolved significantly since their inception in 1979. This paper describes the latest advances appearing in the CHBDC along with the steps taken to calibrate its recent geotechnical resistance and consequence factors.

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Reliability assessment in highway bridge design

Canadian Journal of Civil Engineering ◽

10.1139/l02-079 ◽

2002 ◽

Vol 29 (5) ◽

pp. 799-805 ◽

Cited By ~ 6

Author(s):

M S Cheung ◽

W C Li

Keyword(s):

Reliability Assessment ◽

Highway Bridges ◽

Highway Bridge ◽

Design Code ◽

Bridge Design ◽

Limit States ◽

Safety Level ◽

Reliability Design ◽

Finite Strip Method ◽

Standard Design

The current practice of highway bridge design in Canada is based on limit states design. Ideally, by means of the properly calibrated load and resistance factors specified in the applicable design code, limit states design will yield a consistent and uniform safety level for all designed bridge structures. Some factors neglected in the standard design procedures, however, may have unexpected effects on the reliability of a particular design. In this case, to follow a design code exactly may still lead to a certain degree of underdesign or overdesign. Therefore, the reliability assessment is recommended for each particular design, and a simulation-based approach for this assessment is proposed in this study. Examples are presented to support the afore-mentioned recommendation.Key words: highway bridges, reliability, design code, simulation, finite strip method.

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A Case Study on Evaluating the Performance Criteria of the 2014 Canadian Highway Bridge Design Code

IABSE Symposium, Vancouver 2017: Engineering the Future ◽

10.2749/vancouver.2017.3159 ◽

2017 ◽

Author(s):

Sepideh Ashtari ◽

Carlos Ventura ◽

W. D. Liam Finn ◽

Don Kennedy

Keyword(s):

Performance Criteria ◽

Highway Bridge ◽

Design Code ◽

Bridge Design

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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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Fatigue Considerations in the Ontario Highway Bridge Design Code

Canadian Metallurgical Quarterly ◽

10.1179/cmq.1980.19.1.151 ◽

1980 ◽

Vol 19 (1) ◽

pp. 151-160

Author(s):

Paul F. Csagoly

Keyword(s):

Highway Bridge ◽

Design Code ◽

Bridge Design

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Dynamic loading and testing of bridges in Ontario

Canadian Journal of Civil Engineering ◽

10.1139/l84-101 ◽

1984 ◽

Vol 11 (4) ◽

pp. 833-843 ◽

Cited By ~ 53

Author(s):

J. R. Billing

Keyword(s):

Dynamic Load ◽

Dynamic Testing ◽

Highway Bridge ◽

Vibration Modes ◽

Design Codes ◽

Test Results ◽

Design Code ◽

Bridge Design ◽

Strain Measurements ◽

Bridge Testing

The Ontario Highway Bridge Design Code (OHBDC) contains provisions on dynamic load and vibration that are substantially different from other codes. Dynamic testing of 27 bridges of various configurations, of steel, timber, and concrete construction, and with spans from 5 to 122 m was therefore undertaken to obtain comprehensive data to support OHBDC provisions. Standardized instrumentation, data acquisition, and test and data processing procedures were used for all bridge tests. Data was gathered from passing trucks, and scheduled runs by test vehicles of various weights. Accelerometer responses were used to determine bridge vibration modes, and dynamic amplifications were obtained from displacement or strain measurements. The form of the provisions adopted for dynamic load and vibration was confirmed by the test results, subject to minor adjustment of values. Observations on the distribution of dynamic load, and its relationship to span length and vehicle weight, may provide a basis for future refinement of the dynamic load provisions. If the stiffness of curbs and barrier walls is not included in deflection calculations, bridges designed by deflection could be penalized. Key words: bridges, vibration, bridge testing, bridge design codes.

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