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Page 2 of 4 <br /> 6 Comment#5: It appears that the 9-factor for shear wall dowels and diaphragms were 0.75 on pages A59 <br /> and A60. Per ACI 318-14 Sec 21.2.4.1,a 9-factor of 0.6 is required unless the nominal shear <br /> capacity of the walls is greater than the shear corresponding to the development of the <br /> nominal moment capacity of the shear walls. Please indicate which 9-factor was used in the <br /> design of concrete shear walls as it is not clear in the design calculations provided.Also, <br /> please revise the 9-factors accordingly per AC1318-14 Sec 21.2.4.2 for the diaphragm if the <br /> 9-factor for the shear design of the shear walls have been updated. <br /> Response:Addendum 1 sheets A59-A64 have been revised using"-factors equal to 0.6✓ <br /> for the shear design of the diaphragms.See sheets B10-B15 for the revised calculations. <br /> A"-factor of 0.6,used to calculate the nominal shear capacity of the concrete shear <br /> walls,has been used in the shear wall calculations previously submitted.See added <br /> calculation sheet B16 for additional information. <br /> Comment#6: The response to the comment regarding using a perforated shear wall design indicates that a <br /> solid wall has a series of openings punched through solid wall. These walls, being part of the <br /> seismic force resisting system, are intended to be considered special concrete shear walls and <br /> subject to the provisions of ACI 314 18.10. These walls have individual wall piers between <br /> openings and beam-like elements that form above and below the openings. These wall piers <br /> and beam elements in the shear walls are subjected to the strength and detailing provisions <br /> per ACI 318-14 Sec 18.10.7 for coupling beams and Sec 18.10.8 for wall piers where the <br /> required, even if they are viewed as perforated walls. If these perforated walls are not <br /> intended to contain detailing for individual wall piers and/or coupling beams, it is assumed <br /> that the solid wall elements spanningfloor-to-floor are acting as shear walls. Please clarify <br /> and provide calculations and detailing for these wall piers or beam elements or indicate <br /> where full-height shear walls occur. Please update drawings, details, and shear wall <br /> calculations as required. <br /> Response:The RAM Structural System and RAM Concrete struc . analysis model, <br /> afar- <br /> and current typical wall reinforcing detailing shown on sheees into account <br /> ✓ the fact that we are utilizing a continuous concrete wall with the openings designed as <br /> perforations within a continuous wall. Our analysis also takes into account the design 7 <br /> -1)rD you Putt. requirements of ACI 318-14 Section 18.10 for the vertical wall segment design <br /> TWt. wtc a.c. r requirements.See added calculation sheets B17-B23 for information regarding Section <br /> 9wnrt-ivn i 18.10.8.In the cases where the wall segments are long enough to be designed as walls, <br /> wit, G d Tit <br /> j"' , the reinforcing requirements indicated in detail 2/4.03 also complies with Ordinary <br /> Boundary Element requirements per ACI 318-14 as 6 is less than 0.2 Pc. <br /> We have made revisions to detail 1/S4.03 extending the length of the tie spacing to <br /> extend 18"beyond the top and bottom of openings and revised detail 2/S4.03 to comply <br /> with Section 18.10. <br /> 'KR <br /> - l`El�- e . atc-^rtt <br /> Lochsa Engineering www.lochsa.com 1-866-606-9784 <br />