2713 MAPLE ST A & B 2024-01-08 - Laserfiche WebLink

- - -i4-1 i V /Iik (.4- / ) ) Drew Martin From: Jon Conner <LakeviewSE@outlook.com> Sent: Sunday, October 9, 2022 10:26 PM To: Drew Martin Cc: Ismail Mohammad; Rakeeb Khan; Innovative Touch Kyle Cook Subject: RE: [EXTERNAL] Maple Duplex - Ismail Attachments: Maple Duplex structural calcs pages 221009.pdf; Maple St details-S03.pdf Hi Drew—see attached calc pages and revised detail sheet. You asked for only the revised calcs, so I've deleted the previously submitted sheets. I've broken up your comments below and added responses in blue. If you have additional questions please give me a call to discuss so we can wrap this up. Let me know if you want these responses put on letterhead for your files. 1. The submitted detail appears incomplete, including but not limited to: a. The length of the sistered member is not specified. i. The Sistered member is full height from the existing double plate to the top of the wall and is already installed. b. This member should have sufficiently length and fasteners to develop, at a minimum the flexural strength of the spliced existing stud. i. The sistered member is full height but it does NOT need to have the same flexural strength of the existing stud. The sistered member is simply an extension of the existing stud to span the 12" gap from the existing single plate to the existing double plate.Therefore, it needs to have the flexural capacity to meet the demand on the member within that 12" gap. The flexural demand on the 2x4 is provided in the calculations and is very low because it is only a foot away from the support (double plate). The maximum flexural demand on the stud is at the mid-point of the stud, where the two members are now acting together.These calculations were provided previously and were apparently ignored or not reviewed. The splice development calc has been added to the calculations attached. c. Note that it is understood that the spliced studs are only every other stud, and so they must take both the flexural out-of-plane load and also the buckling resistance for supporting axial loads equivalent to two studs. The proposed splicing of every other stud is strongly not recommended. i. Calcs have been added to show the combined DCR for flexure, shear, and compression is well below 1.0, as expected. Splicing every other stud is OK. d. The removal of the blocking has unclear impacts on the shear load path in the wall sheathing. It is presumed that the sheathing transfers loads to the blocking. i. The load path is the same with or without the blocking. The wall sheathing is not and cannot be fastened to the blocking, therefore the blocking cannot transfer any loads directly into the sheathing. The back wall of the structure is all existing and cannot be accessed to add shear wall nailing into any new blocking. Installing new blocking would simply brace the studs at the floor diaphragm level against torsion. The uniform shear at this location is very low, as previously shown. however rather than run a torsional analysis on the studs, we will just install the blocking. e. Removing this blocking potentially removes the load path as well as eliminates the integrity of the panel itself. The detail needs to show that the integrity of the load path is maintained or replaced in a code- compliant manner. i. The load path is the same regardless of the blocking.The floor diaphragm loads are transferred into the ledger, then the existing studs, and then to the shear wall panels.The blocking simply braces the studs against torsion. Blocking will be installed for stud bracing. 62 )/-- -s- )