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RE: base plate software

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Title: RE: base plate software

>I have base plates on a project with t > 2", due to bending moments.  Plate
>thickness is governed mostly by distance of edge of plate to column edge.
>Are base plate stiffeners warranted due to assumption of uniform stress
>under base plate?

Stress distributions under base plates aren't really uniform, that's just the assumption used in the rational design model that makes the job of the engineer easier when sizing base plates. There are probably hot spots under the base plate in predictable locations (whether stiffeners are used or not). But the resulting local deformations are small and self limiting, assuming the base has been designed properly.

Detail materials like stiffeners add a significant expense because there is a lot of labor associated with each one (both in making them and in welding them). As a general rule of thumb, cost is proportional to the number of detail pieces required for the detail, so if you add four stiffeners, you may be quadrupling the cost of your detail.

Therefore, if a base plate can be selected with a sufficient thickness to eliminate the need for stiffeners, that will be the least-cost solution in the majority of cases.

Charlie