Civil Engineering Reference
In-Depth Information
The test structure should be assembled in accordance with the Manu-
facturer's recommendations. It may be desirable to specify detailed
methods or sequences for the test structure to prove the acceptability of
proposed fi eld erection methods. Pickup points designed into the struc-
ture should be used during erection. Using the pickup points may allow
observation of structure behavior under these construction loads. The
completed structure should be set within the tolerances permitted in the
construction specifi cation.
After the structure has been assembled, erected, and rigged for testing,
the Purchaser should review the testing arrangement for compliance with
the contract documents. Safety guy wires or other safety features may be
loosely attached to the test structure and used to minimize consequential
damage to the structure or to the testing equipment in the event of a
premature failure, especially if an overload test to failure is specifi ed.
The loads to be applied to the test structure should be the loads speci-
fi ed for design and should include all appropriate load factors. Wind-on-
structure loads typically are applied in a test as concentrated loads at
selected points on the structure in a pattern to make a practical simulation
of the in-service uniform loading. The magnitudes and points of applica-
tion of all design loads should be specifi ed in the test procedure. The
loading rate should also be determined and specifi ed in the agreed-upon
test procedure.
Load lines should be attached to the load points on the test structure
in a manner that simulates the in-service load application as much as
possible. The attachment hardware for the test should have the same
degrees of movement as the in-service hardware.
V-type insulator strings should be loaded at the point where the insula-
tor strings intersect. If the insulators for the structures in service are to be
a style that will not support compression, it is recommended that wire
rope be used for simulated insulators in the test. If compressed or canti-
lever insulators are planned for the structures, members that will simulate
those conditions should be used.
As the test structure defl ects under load, load lines may change their
direction of pull. Adjustments must be made in the applied loads so that
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