Note:
This post is a link redirected from an article/document I wrote and submitted to AISC (American Institute Steel Construction) Steel Tools

A post for Structural Engineers and Designers.

Once in a while I will be posting on this blog topics about engineering and structural design that are relevant to my job as structural designer. In this post I am going to share techniques in bolted connection calculation using MS Excel and VBA Codes (Visual Basic for Application).

There are two methods in the analysis of eccentrically loaded bolted connections presented by AISC Steel Construction Manual, namely:

1. The INSTANTANEOUS CENTER OF ROTATION Method; and
2. The ELASTIC Method.

These methods are discussed in AISC Steel Construction Manual and would be redundant if discussion is repeated here.

In designing bolted connections, you may be confronted with both calculation ease and difficulties when you are employing the INSTANTANEOUS CENTER OF ROTATION Method (ICR). The Instantaneous Center of Rotation Method replaces the conservative but more popular ELASTIC Method which has a closed form analytical solution to the strength of the bolt group; meaning, it has an exact formula. The ICR, developed by Crawford and Kulak, is also known as ULTIMATE STRENGTH Method. Compared with the Elastic Method, ICR is found to be more economical since it is based on the ultimate strength of bolts. The only setback that the method has -- is that -- it requires intensive numeric iteration for a solution and cannot be performed by hand alone.