Need a book? Engineering books recommendations...

Return to index: [Subject] [Thread] [Date] [Author]

Re: Side Plate Systems - Eureka Moment

[Subject Prev][Subject Next][Thread Prev][Thread Next]
Title: RE: Side Plate Systems - Eureka Moment
After forwarding Charlie Carter's message to a steel fabricator familiar with the SidePlate System, I received the following message addressed to Charlie:
Charlie: I've read your comments regarding the SidePlate patented moment frame system. I would like to offer my comments regarding the system. Having fabricated four of them, and erected 2 and subcontracted the erection on the other 2, we have a comfort level with the system that we don't have with the dog-bones or other moment frame systems.
From a detailing standpoint, we always know exactly what we have with a SidePlate. The detailing becomes quicker and more efficient because of that. We don't have the number of RFI's generated on a SidePlate that we experience on other designs that pass through our facility, which saves us management time.
Pound for pound, we typically fabricate and erect a SidePlate for the same, or less, cost as other systems. The shop labor is higher, to be sure; however, the field welding is less, so the increase in shop labor is essentially cancelled by the decrease in field labor.
The schedule is impacted in a like manner, with the heavier shop labor consuming more pre-erection time. The reduction in field welding allows the detailing portion of the erection process to proceed more efficiently, thus getting the deck down sooner and allowing other trades to begin their work.
Another advantage of the field welding is realized in inspection costs. With a dog-bone system, an inspector must visit the beam/column moment connection at least four times, while with SidePlate, one UT on each beam splice does the trick.
SidePlate is not without problems. The logistics of transporting very large columns is cumbersome, however can be easily overcome with careful planning and do not significantly increase the costs of fabrication and delivery. 
Certainly there is a learning curve for a fabricator who is working the system for the first time. Developing the sequence of events necessary to build such a system takes time and experience, which is not free. We have developed a method of fabricating the SidePlate columns that has proven quite effective, enabling us to accurately pin down the costs of such a system.
The complexities of the dog bone are not always clear, but one example would be the most recent one we delivered. The structural engineer of record (EOR) insisted that the field welding of the moment connections be with SMAW, rather than FCAW. The cost of SMAW is roughly five times that of FCAW. Another issue is that of material availability. I have yet to see a SidePlate that requires W shapes not available from domestic producers. I don't believe that any other system can make that claim. However, I have yet to see a SidePlate project over five stories tall, and obviously the material requirements for taller structures may require shapes in excess of 400 # per foot.  
A project we fabricated with SidePlate this past Summer might help you see the potential savings that SidePlate has to offer.  This project was already bid and permitted by the City of Los Angeles with the Dogbone system using W14x550 and W14x605 columns.  Since the required lengthy and uncertain procurement lead time was impacting the construction schedule, the EOR contacted SidePlate and requested a redesign using significantly lighter W27x258 and W27x307 columns.  Apparently, SidePlate is prequalified by ICBO and COLA to use any size beam and column.  The bottom line is that we ended up using moment frame beams, columns and plates with SidePlate that were 25% lighter than the original design, saving the owner a net 127 tons, $307,500 in total steel fabrication and erection and kept the project right on schedule.  SidePlate's fee to do the job was $25,000, thus saving the owner a net $282K.
Mike Hockstad
Senior Project Manager
Sampson Steel Constructors, Inc.
Bakersfield, California