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*Commodore John J. Barry Bridge [#n53efd09]

**1.Field of application [#p8c56a3d]

>Commodore John J. Barry Bridge over the Delaware River between Chester, Pa., and Bridgeport, N.J., which is located on the boundary between Pennsylvania and New Jersey, U.S.A. 

**2.Circumstances of repair [#e405dcf7]

>Fatigue cracks were found near the vertical member with the upper chord member in March 1973 during construction. 

**3.Types of structure [#fd654d68]

>The cantilever truss bridge has a 1,644-ft main span that consists of an 822-ft suspended section flanked by two sections that cantilever from reinforced concrete rigid frame piers, and two 822-ft side spans ([[Fig.1>#fig1]]).

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CENTER:&aname(fig1);&attachref(JohnBa32.jpg);&br;
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CENTER:Fig.1 Cantilever truss bridge. 
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**4.Details of loading [#qb74b3e9]

>Fluctuating loads due to wind load.

**5.Description of damage [#fe92e72d]

>Fatigue cracking were found during construction while the trusses were being erected. 

>During this construction, a four-day period of high winds occurred, and some of the secondary truss members vibrated. As a result, some of them developed cracks. 

**6.Repair method applied [#g319d744]

>Temporary restraining cables were installed prior to the opening of the bridge ([[Fig.2>#fig2]]). 

>Because certain other members should be secured, these cables were added in order to increase their resistance to vibration under wind load. 

>After this, dampers were installed and added cables were removed ([[Fig.3>#fig3]]). 

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CENTER:&aname(fig2);&attachref(JohnBa33.jpg);&br;
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CENTER:Fig.2 Temporary restraining cables. 
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CENTER:&aname(fig3);&attachref(JohnBa34.jpg);&br;
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CENTER:Fig.3 Complete view.
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**Reference [#ff51a569]
>'''Engineering News Record,'''Aug., 1, 1974. 
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