Page 277 - Handbook of Structural Steel Connection Design and Details

Welded Joint Design and Production

262 Chapter Three

One approach to obtaining acceptable connections is rigorous con-
trol of each of the material properties. Evidence exists that this can
be done, even under very demanding conditions that simulate earth-
quake loading. There is an acceptable approach, however, that relies
less on rigorous control of the mechanical properties, and compen-
sates for these concerns by geometrically changing the connection.
This alternative is discussed in “Cover-Plated Designs” section.

3.9.6 Workmanship

For severely loaded connections, good workmanship is a key contribu-
tor to acceptable performance. In welded construction, the perfor-
mance of the structural system is often dependent on the ability of
skilled welders to deposit sound weld metal. As the level of loading
increases, dependence upon high-quality fabrication increases.
The role of codes. Design and fabrication specifications such as the
AISC Manual of Steel Construction and the AWS D1.1 Structural
Welding Code—Steel are typical vehicles that communicate minimum
acceptable practices. It is impossible for any code to be so inclusive as
to cover every situation that will ever be contemplated. These codes
and specifications address minimum acceptable standards, relying
upon the engineer to specify any additional requirements that super-
sede these minimum levels.
The D1.1 code does not specifically address seismic issues but does
establish a minimum level of quality that must be achieved in seismic
applications. Additional requirements are probably warranted. These
would include requirements for nondestructive testing and notch
tough weld deposits, and additional requirements for in-process veri-
fication inspection.

Purpose of WPS. Within the welding industry, the term welding pro-
cedure specification, or simply WPS, is used to signify the combina-
tion of variables that are to be used to make a particular weld. The
WPS is somewhat analogous to a cook’s recipe. It outlines the steps
required to make a good-quality weld under specific conditions. It is
the primary method to ensure the use of welding variables essential
to weld quality. Also, it permits inspectors and supervisors to verify
that the actual welding is performed in conformance with the con-
straints of the WPS.
Prior to the start of welding on a project, WPSs typically are sub-
mitted to the engineer for review. Many engineers with limited
understanding of welding will delegate this responsibility to other
individuals, often the owner’s supplied inspection firm, to verify the
suitability of the particular parameters involved. For critical pro-
jects, the services of welding engineers may be appropriate. Most

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