Hi JPM,
Wind loading and design for wind-resistant structures, very little. Most of my related work has been FEA for vibration resistance of airframe-mounted electronics and optical instruments. Also large super-stable optical metrology systems. But very little experience in things like highway signs, buildings, silos, etc. I got the conditions (wind speeds) for my area from the ATC Hazards by Location website, which lists ASCE 7-16, ASCE 7-10, and ASCE 7-05 speeds for various MRI year categories and Risk Categories. Also my local AHJ publishes the required wind load and snow load conditions (plus seismic zone etc) to be met here. Their requirement is 90 MPH, Exposure C. For my area the ATC document shows the highest wind speed for Risk Category II (residences) as 115 MPH under ASCE 7-19. I have collected quite a bit of reference information, such as the ANSI/SPRI Wind Design Standard Practice for Roofing Assemblies. There is also an excellent piece by Robert Paullus of Paullus Structural Consultants, his "WIND WEBINAR SERIES #3", from February 2013, that I found online, which is practically a tutorial on designing for wind loading; very helpful! Using Paullus' presentation material (which is available elsewhere in textbooks) I generated a spreadsheet that combines the various factors and gives me the wind load pressure in PSF as well as the total force in pounds for a given area, after entering the wind speed in MPH.
The only design work I've had signed off by a PE to date has been several timber frame home designs back in the 1990s; none of my usual consulting work requires PE. However as I stated above, this solar mounting system will need "an engineered design by an Arizona Registrant for the foundation/footing system. The design shall include attachment to foundation (anchor bolts, size), and number of bolts, embedment depth, size and amount of reinforcement steel, depth and size of foundation/footing." So while the actual statement seems to refer ONLY to the foundation and footing system, I would think they intend for the whole rack or tracker to be so engineered. I need to go speak with someone at Building Safety and get some clarification, before spending real money on either PE design work or the construction itself.
Wind loading and design for wind-resistant structures, very little. Most of my related work has been FEA for vibration resistance of airframe-mounted electronics and optical instruments. Also large super-stable optical metrology systems. But very little experience in things like highway signs, buildings, silos, etc. I got the conditions (wind speeds) for my area from the ATC Hazards by Location website, which lists ASCE 7-16, ASCE 7-10, and ASCE 7-05 speeds for various MRI year categories and Risk Categories. Also my local AHJ publishes the required wind load and snow load conditions (plus seismic zone etc) to be met here. Their requirement is 90 MPH, Exposure C. For my area the ATC document shows the highest wind speed for Risk Category II (residences) as 115 MPH under ASCE 7-19. I have collected quite a bit of reference information, such as the ANSI/SPRI Wind Design Standard Practice for Roofing Assemblies. There is also an excellent piece by Robert Paullus of Paullus Structural Consultants, his "WIND WEBINAR SERIES #3", from February 2013, that I found online, which is practically a tutorial on designing for wind loading; very helpful! Using Paullus' presentation material (which is available elsewhere in textbooks) I generated a spreadsheet that combines the various factors and gives me the wind load pressure in PSF as well as the total force in pounds for a given area, after entering the wind speed in MPH.
The only design work I've had signed off by a PE to date has been several timber frame home designs back in the 1990s; none of my usual consulting work requires PE. However as I stated above, this solar mounting system will need "an engineered design by an Arizona Registrant for the foundation/footing system. The design shall include attachment to foundation (anchor bolts, size), and number of bolts, embedment depth, size and amount of reinforcement steel, depth and size of foundation/footing." So while the actual statement seems to refer ONLY to the foundation and footing system, I would think they intend for the whole rack or tracker to be so engineered. I need to go speak with someone at Building Safety and get some clarification, before spending real money on either PE design work or the construction itself.
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