301 N Broadway - Shell & Core - Plan

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3rd & Broadway, Santa Ana, CA Volume 2 - Structural Calculations June 17, 2024 | Project # S21043.00 pg. 48 4.4 ETABS RESULTS: VERIFICATION OF HORIZONTAL IRREGULARITIES Type Description Applicable RESI / HOTEL Impact on Structure 1a. Torsional Irregularity: Torsional irregularity is deﬁned to exist where the maximum story drift, computed including accidental torsion with Ax = 1.0, at one end of the structure transverse to an axis is more than 1.2 times the average of the story drifts at the two ends of the structure. Torsional irregularity requirements in the reference sections apply only to structures in which the diaphragms are rigid or semi rigid. Yes / Yes RESI/HOTEL: Design forces to be increased by 25% for connection of diaphragms to vertical elements and collectors, their connections and ELF method not permitted. 1b. Extreme Torsional Irregularity: Extreme torsional irregularity is deﬁned to exist where the maximum story drift, computed including accidental torsion with Ax = 1.0, at one end of the structure transverse to an axis is more than 1.4 times the average of the story drifts at the two ends of the structure. Extreme torsional irregularity requirements in the reference sections apply only to structures in which the diaphragms are rigid or semi rigid. No / No - 2. Reentrant Corner Irregularity: Reentrant corner irregularity is deﬁned to exist where both plan projections of the structure beyond a reentrant corner are greater than 15% of the plan dimension of the structure in the given direction. Yes / No RESI: Design forces to be increased by 25% for connection of diaphragms to vertical elements and collectors, their connections at levers where irregularity occurs 3. Diaphragm Discontinuity Irregularity: Diaphragm discontinuity irregularity is deﬁned to exist where there is a diaphragm with an abrupt discontinuity or variation in stiffness, including one having a cutout or open area greater than 50% of the gross enclosed diaphragm area, or a change in effective diaphragm stiffness of more than 50% from one story to the next. No / No - 4. Out-of-Plane Offset Irregularity: Out-of-plane offset irregularity is deﬁned to exist where there is a discontinuity in a lateral force-resistance path, such as an out-of-plane offset of at least one of the vertical elements. No / No - 5. Nonparallel System Irregularity: Nonparallel system irregularity is deﬁned to exist where vertical lateral force- resisting elements are not parallel to the major orthogonal axes of the seismic force-resisting system. No/ No -