9911 23RD AVE SE 2021-12-15 - Laserfiche WebLink

4. On page 18 of the permit calculations, the design uplift pressure due to wind is computed at approximately 46 psf. However, the design roof dead load is computed at 20 psf. Please verify if the roof trusses need to be designed for the net wind uplift pressures as this would place the top and bottom chords of the roof trusses in tension and compression, respectively. 5. Please provide checks for the vertical reinforcement in masonry walls to resist overturning moments developed from in -plane shear. ✓ 6. It appears that the structure has a flexible diaphragm and the "ka" amplification factor equation of 12.11-2 in ASCE 7-10 was not applied to determine the design demand for anchorage forces. Please update the anchorage forces and details as required. 7. Please verify and identify which members are chord members in the roof diaphragm that are resisting the diaphragm design demand moment of 88.8 k-ft. ✓ 8. The addition of the concrete corbel appears to create additional moments out -of plane in the masonry walls. Please verify that the masonry walls are able to resist these moments. 9. It appears that the diaphragm design demand as shown on page 14 of the permit calculations is taking a 0.91 factor to the factored (ultimate/LRFD) diaphragm demand. Please clarify, as ASCE 7-10 Sec 12.4.2.3 does not describe a reduction factor. 10. Please provide clarifications to the factored (ultimate/LRFD) 234 plf diaphragm design demand as the factor of (2) or (dividing by 0.5) is reserved to compare to nominal design capacities if the design demands were evaluated at ASD levels. If factored (ultimate/LRFD) values are to be used, please compare nominal capacities at the factored (ultimate/LRFD) levels. Sincerely, )am s Bronder, PE As iate Engineer M-' ^= Pla Examiner -+- Page-2 of CITY OF EVERETr • 3200 Cedar Street • Everett, WA 98201 • (425) 257-8810 • Fax (425) 257-8857 W