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RE: Side Plate Systems - Eureka Moment

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I have read the on-going discussion of the SidePlate connection with great interest. In the past six years, I have designed six major buildings using the connection. My experience with the connection also led me to the unique idea of using it for the preventing progressive collapse of floors due to a blast or other catastrophic event.  I offer the following comments to those who have not designed a building with the connection system or have reservations about using a proprietary system:

My project experience with connection has been exceptionally good in every case. Any initial fabricator concerns were quickly eliminated when SidePlate technical support provided useful in-shop & transportation advice.  I always found that the fabrication/erection price for moment frames to be as cheap or cheaper than frames involving connections with full penetration welds.  Furthermore, the steel was erected more quickly.  In every case, the fabricator expressed the strong wish to do another building with the connection.  

Never have I felt, nor has any fabricator, owner, or contractor expressed any comment that the SidePlate connections looked as if "it were built like a tank". Whether used for seismic or progressive collapse purposes, I have always found the connection elements and welds to be proportionally reasonable.

The proprietary nature of the connection seems to elicit strong feelings among many engineers.  It is important to remember that the fee associated with using the connection includes a valuable service and technical support for the engineer of record during the design, permitting, and construction of the project.  The private, county government, and federal government clients that I worked for did not have a problem paying the nominal fee for the using the connection when they understood the development costs and the services provided with the connection.  Engineers commonly specify pre-engineered buildings, prestressed and precast concrete, steel joists, and other systems that have built-in design fees included in the cost. MEP engineers use patented products all the time. If the client ultimately benefits (both functionally & economically) from this, so what if it is patented.  If the SidePlate fee did not include connection design services, pre-bid services, pre-construction services, construction services, permitting services, and shop drawing review services, then I might have similar feelings like those expressed in other email.  

With respect to blast design, I envisioned the use of the SidePlate connection combined with tube or box columns filled with lean or conventional concrete a an economical alternative to concrete frame systems. I authored a paper published in the proceedings of 1999 SEAOC Annual Conference describing the system and its use on a new federal courthouse in Texas. The system was developed in order to prevent progressive collapse of the floors due to the loss of a column.  The concrete filled tube or box columns are intended to be an economical means of toughening the column against blast. The SidePlate connection does not rely upon any through-thickness strength, groove welds, or internal diaphragm plates, and it can easily develop plastic hinges at the ends of the beams and can develop axial forces from the cantenary action that results from the lost column.  Blast design requires a redundant structural system and the one I have described can provide this very economically. The blast design concept was reviewed and highly endorsed by an internationally eminent blast consultant.  Since their review, this concept has been very accepted by blast consultants as a simple, straight-forward approach to blast design. It has also been implemented on other gonvernment projects by other consultants.  

I have attempted to describe how economically effective the SidePlate connection system can be. To assume it is naturally bulky,expensive, and expensive to build & erect is wrong. To dismiss it due to feelings related to its licensing use takes away an significantly important option to a client.  I think engineers should be able to responsibly evaluate and recommend appropriate solutions for their clients. At times that may require solutions that are not traditional.

S. Punch, P.E.
Dallas, TX