Author Archives: Dan Popp

When Is a Wall a Column?

So there you are, designing away, when you come across a strange bird: a very long column. Or is it a very short wall? Where exactly is the line between the two? The implications can be significant: · Columns require … Continue reading

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Congratulations to CBRE on occupying your sparkling new office space atop 321 North Clark in Chicago. Thanks for letting us be part of the team.

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ETABS 2013 One Year Later

It’s been a year since CSI released the long-awaited next generation of ETABS. My colleagues and I have poked and prodded ETABS 13 for thirteen months and like what we’ve seen. I’ve watched the release notes and seen many bugs squashed. But as … Continue reading

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Top Ten Reasons Engineers Don’t Specify HSS

I recently had the privilege of attending the annual conference of the Steel Tube Institute. As a member of the technical committee, I was asked to present a structural engineer’s perspective on why engineers don’t use tubes, er, HSS. The … Continue reading

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ETABS 2013 to SAP

In ETABS 9, it was possible (although not easy) to import a model to SAP. ETABS 2013 does not yet offer this capability directly, but CSI is developing an ETABS-SAP translator. They graciously shared a beta version with me, and … Continue reading

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Dear New York, Congratulations on taking the title away from us. You’ve been through a lot, and you deserve it. This race isn’t over yet, though. Your friend, Chicago P.S. Our pizza is still better.

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Bad Function Data in ETABS 2013

It sounds like an obscure hipster band name, but it’s actually an error you may see in ETABS 2013: “Bad Function Data”: This will occur if you import an ETABS 9 model with an auto-generated response spectrum function (e.g., an … Continue reading

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ETABS 2013 Model Downgrade to ETABS 9

You and I both want to use ETABS 2013 and gain access to the faster analysis times and new features. But we haven’t made the plunge, at least in part because we might lose work if we get a week … Continue reading

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Importance Factor for Large Office Buildings

This question seems to come up quite often: what importance factor should be used for a large office building? The answer is apparently less than clear. Here’s my take: The intent of the 2006 IBC is to require Occupancy Category … Continue reading

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ETABS 2013 Disorder

CSI changed the default background color in ETABS 13 to white. If this really bothers you and you feel a compulsion to change it back, just use the following easy-to-remember keyboard sequence: Alt+O,C,D What do you think: coincidence or CSI … Continue reading

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