Hi,
I am using to design Baseplate and anchorage to concrete with epoxy anchors. My goal is to design my base plate so that it go under the plastic strain. I was wondering what is the limit of 5% for plastic strain from? what is the reference?
Also how can I adjust it to fit for my purpose. the application of my design is not building structure base plate.
Also, I want to know how accurate is the Hilti Profis in terms of determining the plastic strain of the anchor plate and profile. (my profile (Pipe) is compact D/t=16.2, ant it is less than 2.5ft tall)
Hi Ali,
The behavior of the steel is based on a bilinear stress strain curve as shown in green (image attached). Once the Fy is exceeded on the linear portion of the curve, plastic strain is activated in the plate and the user can control the amount of this plastic strain by choosing a limit in the graphics user interface under “Advanced Settings”. The US model codes do not address the topic of plastic strain limit for steel design, but the Eurocode suggests a 5% limit. The user can therefore put any limit as per his/her experience and once that limit is exceeded the user would presumably consider the results unfavorable for an ACI based model code check. This should be coupled with looking at the max plastic deformation. Together, these two parameters can assist an experienced user in making a sound engineering judgement as far as anchorage design is concerned.
For more information on the CBFEM analysis in PROFIS Engineering, please review this article from Structure Magazine which was written by one of the software product developers/managers at Hilti.
Regards,
Dani
