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LaGuardia Airport
Load Tes t i ng of Runway Ex tens i on
The runway system at LaGuardia Airport was extended over Long Island Sound in the early 1960s. This over-water runway extension was a historic
structural achievement, chosen by the Precast/Prestressed Concrete Institute as one of the fifty most significant projects in its fifty-year history. The
precast concrete girders that support the runway extension were exposed to an aggressive chloride environment from partial submersion in seawater
twice a day. Consequently, the girders began to deteriorate due to corrosion of the embedded prestressing strands. To restore the girders to their original
strength, the Port Authority of New York and New Jersey developed plans to retrofit the girders with a composite steel trough. WJE was retained to
perform load tests and determine the feasibility of the retrofit design.
For more than thirty years, the Port Authority has continued to call on WJE to test the runway extension because its complex structural behavior
has defied their best efforts to analyze it with conventional analytical computer programs. While WJE has tested many structures over the years,
few projects match the scope and complexity of the work performed at LaGuardia.
Notes of Interest
• Two full-scale retrofitted girders were tested to failure in
the five million pound test machine at Lehigh University.
• The failure mode of the test girders prompted a
redesign of the retrofit details to improve the shear
strength of the girders.
• LaGuardia Airport was named after Fiorello LaGuardia,
the mayor of New York from 1934 to 1945. LaGuardia was
instrumental in restoring the economic stability of the city
during and after the Great Depression.
• First occupied by Gala Amusement Park, the site was
turned into a 105-acre private flying field in 1929. Ground
was broken on September 9, 1937, for a new airport.
• LaGuardia Airport has been operated by the Port Authority
of New York and New Jersey under a lease with the City of
New York since 1947.
WJE 50 Years