The Tacoma Narrows is the single point in
the 20,000 square miles of Puget Sound where the Washington mainland
and the Olympic Peninsula are close. For years, it had been clear to
State officials that the Narrows would have to be bridged in order to
open up the spectacular and thinly populated Peninsula. Aware of this
situation, the Washington State Legislature created the Washington Toll
Bridge Authority in 1937, with a mandate to finance, construct and
operate toll bridges.
The first Tacoma Narrows Bridge was
revolutionary in its design and historic in its collapse. The failure
on November 7, 1940 marked the end of a trend in bridge engineering
towards a maximum of lightness, grace and flexibility. Since the turn
of the century, suspension bridge construction valued structural grace
and slenderness to achieve an artistic appearance. With its shallow
stiffening trusses and slender towers, the bridge across the Narrows
was the epitome of artistry in bridge construction.
The Tacoma Narrows Bridge was known for its
tendency to sway in windstorms. The shape of the bridge was much like
that of an aircraft wing and under windy conditions it would generate
sufficient lift and become unstable. On November 7, 1940 a large
windstorm caused severe and catastrophic failure if the bridge deck.
The significance of the first Tacoma Narrows
Bridge, to a large extent, is derived from its startling collapse on
November 7, 1940. The collapse brought engineers world-wide to the
realization that aerodynamic phenomena in suspension bridges were not
adequately understood in the profession nor had they been addressed in
this design. New research was necessary to understand and predict these
forces. The official investigation into the collapse recommended the
use of wind-tunnel tests to aid in the design of the second Tacoma
Narrows Bridge and resulted in the testing of all existing and future
bridges across the country. New mathematical theories of vibration,
aerodynamics, wave phenomena, and harmonics as they apply to bridge
design arose from these studies.
Tacoma Narrows Bridge
The collapse of the Tacoma Narrows Bridge
was a hallmark in the history of bridge design and civil engineering.
The remains, located on the bottom of the Sound, are a permanent record
of man's capacity to build structures without fully understanding the
implications of the design and the forces of nature.
of the Bridges
UAS gathered and produced material for the
submission of the collapsed and submerged Tacoma Narrows Bridge to the
National Registry of Historical places. The nomination was the first of
its type, using sonar imagery as the basis for the nomination. The
Nomination was accepted, adding the site to the Federal, State, County
and City Registry of Historical Places. A documentary was prepared and
aired Nationally. The documentary was nominated and won the 1991, 13th
Annual Award For Cable Excellence ( ACE Award).
For a look at this and other local
historical events, please consult the Gig Harbor Peninsula Historical
Society & Museum.
Historical Society & Museum