Carport Structure Collapse in Houston on 1-23-2019

This structure fell down in our office parking lot today after no high wind warnings etc.

Thank God no one was hurt or no cars were damaged as this happened early morning or midnight.

Sad to see a structure fall down here in our parking lot but lots to learn from it. I hope the engineer who designed it also learns from it and will try to make necessary corrections. I modelled it in GT STRUDL using hot rolled sections. They seem to have very flimsy galvanized sections and the structure does not seem to be braced well either. A damaged Ferrari under that carport structure would cost more than the structure itself and a passenger sleeping in the car while this happened would definitely lead to injury.  

During my lunch time, I was able to design the structure to withstand 150 mph wind which could become a norm soon. Wind Load was generated using GT STRUDL’s ASCE Wind Load Generator but hand calculations were performed to account for uplift as per ASCE 7-10 (Assumed Exp. Cat C). Two load combinations were studied as per ASCE 7-10. AISC 14th Ed code was used to account for residual stresses and non-linear effects such as deflection of the structure due to wind and amplified moment due to selfweight. This is a classic case of that effect. You can see the formation of plastic hinges at the places where the moment was maximum. The displacements would be about 1-1.5 in max in this case. I also placed some small columns and tried a few bracing patterns. GT STRUDL selected the sizes that would work for this type of loading.  

Finally, because we had a physical model created in GT STRUDL, the entire model was imported in CAD Worx Structure for drawing generation. All that in one hour! No matter what software they use, they need to use their wisdom to make sure this does not happen. But software can certainly make the process easier and fun for the engineers and designers so that they can concentrate on more important things.