ON AERODYNAMIC STABILITY EFFECTS FOR BLUFF RECTANGULAR CYLINDERS BY THEIR CORNER-CUT

The Angus L. Macdonald Bridge, a major suspension bridge that crosses Halifax Harbour in Halifax, Nova Scotia, opened to traffic in 1955. The bridge deck has reached the end of its service life, and the design of the new bridge superstructure and its replacement sequence were completed in 2014. The entire suspended structure and hangers are now being replaced sequentially during night and weekend closures while the bridge is opened for traffic during the daytime. The erection sequence is supported by sophisticated automated erection analysis models which take into account the geometry of the existing bridge, positioning of the erection equipment on the deck, and hanger and strand jack adjustments that are required during construction. Significant wind tunnel testing and analysis have been performed to ensure aerodynamic stability of the bridge during erection and in its final condition.

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The Third Bosporus Bridge — the Aerodynamic Stability of the Steel Segments During the Lifting

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

10.2749/newyork.2019.2656 ◽

2019 ◽

Author(s):

Vincent de Ville de Goyet ◽

Yves Duchêne

Keyword(s):

Vertical Axis ◽

Longitudinal Axis ◽

The Black Sea ◽

Span Length ◽

Geometrical Configuration ◽

Aerodynamic Stability ◽

The Third ◽

The North ◽

Torsional Instability ◽

Main Cables

<p>The Third Bosporus Bridge is a suspendion bridge with a main span length of 1 408 m and a total length of 2 408 m located at the north of Istanbul near the Black Sea.</p><p>The main span is partially suspended at the pylons by stiffening cables and at the main cables with vertical hangers (Fig.1‐2). The deck is 58.8 m wide. But contrary to a classical arrangement, the transversal distance between the vertical hangers, in the suspended zone, is only 13.50 m. Due to this geometrical configuration of the vertical hangers, it was necessary to verify the risk of aeroelastic instabilities of steel segments of the deck during its lifting: risk of a torsional instability around the longitudinal axis but also around the vertical axis. Countermeasures have been proposed and adopted to suppress these risks.</p>

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Aerodynamic Stability of Suspension Bridges: 1952 Report of the Advisory Board on the Investigation of Suspension Bridges

Transactions of the American Society of Civil Engineers ◽

10.1061/taceat.0007255 ◽

1955 ◽

Vol 120 (1) ◽

pp. 721-781

Author(s):

Keyword(s):

Advisory Board ◽

Suspension Bridges ◽

Aerodynamic Stability

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Ensuring the aerodynamic stability of the long-span bridges through studies in the wind tunnel

MATEC Web of Conferences ◽

10.1051/matecconf/201824502001 ◽

2018 ◽

Vol 245 ◽

pp. 02001 ◽

Cited By ~ 1

Author(s):

Evgenii Khrapunov ◽

Sergei Solovev

Keyword(s):

Wind Tunnel ◽

Design Process ◽

Aerodynamic Characteristics ◽

Elastic Instability ◽

Experimental Facility ◽

Bridge Design ◽

Aerodynamic Stability ◽

Long Span Bridges ◽

Long Span ◽

Main Ideas

The main ideas of the aerodynamic studies of large bridges are presented in present paper. Main types of aero-elastic instability for bridges with spans over 100 meters are considered. A two-step modeling approach is presented. At the first stage, the aerodynamic characteristics of the span fragment are considered, at the second.stage the characteristics of the whole bridge. Methods for investigation of bridge oscillations in a special-purpose experimental facility – the Landscape Wind Tunnel – are described. Examples of tests with elastic similar models of bridges are given, and measurements to mitigate dangerous oscillations early in the bridge design process are described.

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ON AERODYNAMIC STABILITY EFFECTS FOR BLUFF RECTANGULAR CYLINDERS BY THEIR CORNER-CUT