Section 304A — STRUCTURAL DESIGN LOADS AND EVALUATION AND DESIGN PROCEDURES

304 A .1 Live loads. Where an addition or alteration does not result in increased design live load, existing gravity load-carrying structural elements shall be permitted to be evaluated and designed for live loads approved prior to the addition or alteration. If the approved live load is less than that required by Section 1607 A of the California Building Code, the area designated for the nonconforming live load shall be posted with placards of approved design indicating the approved live load. Where the addition or alteration results in increased design live load, the live load required by Section 1607 A of the California Building Code shall be used.

304 A .2 Snow loads on adjacent buildings. Where an alteration or addition changes the potential snow drift effects on an adjacent building, the code official is authorized to enforce Section 7.12 of ASCE 7.

304 A .3 Additions, alterations, repairs and seismic retrofit to existing buildings or structures.

304 A .3.1 Structures designed in accordance with pre-1973 building code. Provisions of this section shall apply to hospital build- ings which were originally designed to pre-1973 building codes and not designated as SPC 3 or higher in accordance with Chapter 6 of the California Administrative Code.

304A.3.1.1 Incidental and minor structural alteration, additions, or repairs. Incidental and minor structural additions shall be permitted, provided the additions meet the California Building Code for new construction using importance factor, I e , equal to or greater than 1.0. Alterations or repair to existing gravity and lateral force-resisting systems shall be made to conform to the requirements of Section 503A or Chapter 4A, respectively, using importance factor, I e , equal to or greater than 1.0. 1. Nonstructural components. Component importance factor, I p , shall be permitted to be 1.0.

Exception: Components required for life-safety purposes after an earthquake, including emergency and standby power systems, mechanical smoke removal systems, fire protection sprinkler systems, fire alarm control panels and egress stairways shall have a component importance factor (I p ) of 1.5.

304A.3.1.2 Major structural alteration, additions or repairs. Major structural alterations, additions or repairs shall be in accor- dance with Section 304A.3.4.1 or 304A.3.4.3 as applicable.

304A.3.2 Seismic evaluation and retrofit of general acute care hospitals for compliance with the California Administrative Code, Chapter 6. Notwithstanding any other requirements of this code, existing general acute care hospitals shall comply with the seismic evaluation requirements specified in Chapter 6, of the California Administrative Code, when applicable. Seismic retrofit to comply with requirements specified in Chapter 6 of the California Administrative Code shall be permitted to be in accordance with these provisions. When load combinations which do not include seismic forces are required, the new building provisions of this code shall be applicable.

3A-4 2025 CALIFORNIA EXISTING BUILDING CODE

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

PROVISIONS FOR ALL COMPLIANCE METHODS

304A.3.3 SPC-4D. Nonconforming hospital buildings satisfying the following requirements and one of Sections 501A.3.1, 501A.3.2 or 304A.3.4.5, but not a combination thereof, shall be considered to satisfy the requirements of SPC-4D. 1. Approval of construction documents based on building characterization in accordance with the California Administrative Code (CAC) Chapter 6 Section 2.1.2.1, material properties in accordance with the CAC Chapter 6 Section 2.1.2.2 and Section 304A.5.3 of this code, and a complete rational structural analysis shall be required. 2. Where the SPC-4D upgrade involves construction, a building permit prior to construction shall be required. 3. Where multiple building permits are used to upgrade a building to SPC-4D, a complete rational structural analysis to justify compliance with SPC-4D, for the building in its final configuration, shall be submitted as part of the construction documents submittal to the Office for the last project. 4. Where the SPC-4D upgrade involves construction, buildings shall be assigned to SPC-4D after all projects required for SPC- 4D are closed in compliance.

304A.3.4 Performance objectives of performance-based methods. Except for the modifications as set forth in Sections 304A.3.4, 304A.3.5 (for ASCE 41-13), and 304A.3.6 (for ASCE 41-23) of this code, all additions, alterations, repairs and seismic retrofit to existing structures or portions thereof shall be permitted to be designed in accordance with the provisions of ASCE 41-23.

Use of ASCE 41-13 shall be limited to SPC-2 and SPC-4D buildings only.

When load combinations which do not include seismic forces are required, the new building code provisions of the California Building Code shall be applicable. Required building performance objectives under ASCE 41-23 shall be as follows:

304A.3.4.1 For general acute care hospital buildings along with all structures required for their continuous operation or access/egress: 1. Immediate Occupancy (IO) Structural Performance Level (S-1) in accordance with ASCE 41-23 Table 2-1 at Basic Safety Earthquake 1N (BSE-1N) Seismic Hazard Level; and 2. Life Safety (LS) Structural Performance Level (S-3) in accordance with ASCE 41-23 Table 2-1 at Basic Safety Earthquake 2N (BSE-2N) Seismic Hazard Level; and

3. The nonstructural components shall satisfy the requirements of this code for new construction.

Exception: Performance objectives for upgrading nonconforming hospital buildings to SPC-4D and for incidental or minor alter- ations or repairs of SPC-4D buildings shall be in accordance with Section 304A.3.4.5 of this code.

304A.3.4.2 For incidental and minor additions, alterations or repairs of pre-1973 hospital buildings which will not be used for general acute care services after January 1, 2030 using ASCE 41-13: 1. Life Safety Structural Performance (S-3) Level in accordance with ASCE 41-13 Section 2.3.1.3 at the Basic Safety Earth- quake 1E (BSE-1E) Seismic Hazard Level; and 2. Collapse Prevention (CP) Building Performance Level (S-5) in accordance with ASCE 41-13 Section 2.3.3.4 at the Basic Safety Earthquake 2E (BSE-2E) Seismic Hazard Level; and 3. The nonstructural components shall satisfy the requirements of Position Retention Nonstructural Performance Level (N-B) in accordance with ASCE 41-13 Section 2.3.2.2 at BSE-1E Seismic Hazard Level.

304A.3.4.3 All other hospital buildings: 1. Immediate Occupancy Structural Performance level and Operational non-structural performance level (1-A) in accor- dance with Table 2-5 at Basic Safety Earthquake 1N (BSE-1N) Seismic Hazard Level; and 2. Life Safety (LS) Structural Performance Level (S-3) in accordance with Table 2-1 at Basic Safety Earthquake 2N (BSE-2N) Seismic Hazard Level.

304A.3.4.4 SPC 2 using ASCE 41-13. Structures shall be considered to comply with SPC 2 requirements of Table 2.5.3, Chapter 6 of the California Administrative Code, when all of the following are satisfied: 1. Life Safety Structural Performance Level (S-3) in accordance with Section 2.3.1.3 of ASCE 41-13 at BSE-1E; and 2. Items identified in Chapter 6, Article 10 of the California Administrative Code satisfying the requirements of Position Retention nonstructural Performance Level (N-B) in accordance with Section 2.3.2.2 of ASCE 41-13 at BSE-1E.

de, when all of the following are satisfied:_ 1. Life Safety Structural Performance Level (S-3) in accordance with Section 2.3.1.3 of ASCE 41-13 at BSE-1E; and 2. Items identified in Chapter 6, Article 10 of the California Administrative Code satisfying the requirements of Position Retention nonstructural Performance Level (N-B) in accordance with Section 2.3.2.2 of ASCE 41-13 at BSE-1E.

304A.3.4.5 SPC-4D using ASCE 41-13. Structures shall be deemed to comply with the SPC-4D requirements of Table 2.5.3, Chapter 6 of the California Administrative Code, when all of the following requirements in ASCE 41-13 are satisfied: 1. Damage control Structural Performance Level (S-2) in accordance with Section 2.3.1.2.1 of ASCE 41-13 at BSE-1E; and 2. Collapse Prevention Structural Performance Level (S-5) in accordance with Section 2.3.1.5 of ASCE 41-13 at BSE-2E; and 3. Items identified in Chapter 6, Article 10 of the California Administrative Code satisfy the requirements of Position Reten- tion Nonstructural Performance Level (N-B) in accordance with ASCE 41-13 Section 2.3.2.2 at BSE-1E.

304A.3.4.5.1 Replace ASCE 41-13 § 7.2.13.2 with the following: A. Where the adjacent building was constructed using the 1989 or later edition of the California Building Code and built under OSHPD jurisdiction, the minimum building separation distance specified in Section 7.2.13.1 need not be evalu- ated for Structural Performance Level Damage Control or lower.

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

PROVISIONS FOR ALL COMPLIANCE METHODS

B. Where adjacent structure or building evaluated is not less than half as tall and adjacent structure has floors/levels that match those of the building being evaluated, the following exceptions apply: 1) For Structural Performance Level of Life Safety or lower, the seismic separation between the adjacent structure and the building being evaluated need not be evaluated. 2) For Structural Performance Level of Damage Control, buildings need not meet the minimum separation distance specified in Section 7.2.13.1 where either a) or b) applies: a) Adjacent structure is more than 2 inches (50.8 mm) times the number of stories below that level away from the building being evaluated at all floor levels that align. b) The adjacent building does not have any of the following structural deficiencies as defined in the Califor- nia Administrative Code (CAC), Chapter 6, Article 3: 1) Load path (3.1) 2) Weak story (3.3.1) 3) Soft story (3.3.2) 4) Vertical discontinuity (3.3.5) or 5) Torsion (3.3.6) C. Where an approved pounding analysis procedure that accounts for the change in dynamic response of the structures caused by impact is used, the evaluated and retrofitted buildings need not meet the minimum separation distance specified in Section 7.2.13.1. Such analysis shall demonstrate that: 1) The structures are capable of transferring forces resulting from impact for diaphragms located at the same elevation; or

nalysis procedure that accounts for the change in dynamic response of the structures_ caused by impact is used, the evaluated and retrofitted buildings need not meet the minimum separation distance specified in Section 7.2.13.1. Such analysis shall demonstrate that: 1) The structures are capable of transferring forces resulting from impact for diaphragms located at the same elevation; or

2) The structures are capable of resisting all required vertical and lateral forces considering the loss of any elements or components damaged by impact of the structures.

304A.3.4.6 SPC 5 using ASCE 41-23. Structures shall be considered to comply with SPC 5 requirements of Table 2.5.3, Chapter 6 of the California Administrative Code where all of the following are satisfied: 1. Immediate Occupancy Structural Performance Level (S-1) in accordance with ASCE 41-23 Table 2-1 at BSE-1N; 2. Life Safety Performance Level S-3 in accordance with ASCE 41-23 Table 2-1 at BSE-2N; and 3. Items identified in Chapter 6, Article 10 of the California Administrative Code, satisfying the requirements of Operational Nonstructural Performance Level (N-A) in accordance with ASCE 41-23 Table 2-2 at BSE-1N.

304A.3.4.7 NPC-2 and NPC-3 using ASCE 41-23: Operational Nonstructural Performance Level (N-A) and Position Retention Nonstructural Performance Level (N-B) of ASCE 41-23 at BSE-1N shall be considered equivalent to NPC 3/NPC 2 requirements, respectively, of Table 11.1, Chapter 6 of the California Administrative Code. For NPC 3/NPC 2, only components listed in Table 11.1, Chapter 6 of the California Administrative Code for NPC 3 / NPC 2 need to satisfy the requirements specified above.

Exception: Evaluation procedure of Article 11, Chapter 6 of the California Administrative Code shall be used for seismic evalua- tion of NPC 2, NPC 3, NPC 4 or NPC 4D and NPC 5, where specific procedure is not outlined in ASCE 41-23. Administrative and permitting provisions outlined in Article 11, Chapter 6 of the California Administrative Code shall apply.

304A.3.4.8 NPC-4 or NPC 4D and NPC-5 using ASCE 41-23: Nonstructural components for Operational Nonstructural Perfor- mance Level (N-A) in ASCE 41-23 Table 2-2 or NPC-4/NPC 4D shall satisfy the requirements of the California Building Code for new construction. Nonstructural components for NPC-5 shall satisfy Operational Performance Level N-A/NPC-4/NPC 4D and California Building Code Section 1617A.1.40 Items 1 & 2.

304A.3.5 Modifications to ASCE 41-13 for SPC-2 and SPC-4D. The text of ASCE 41-13 shall be modified as indicated in Sections 304A.3.5.1 through 304A.3.5.17.

304A.3.5.1 ASCE 41-13 Section 1.1. Modify ASCE 41-13 Section 1.1 with the following:

Seismic evaluations shall be performed for performance objective specified in Section 304A.3.4 of this code (CEBC) using proce- dure of this standard (ASCE 41) as follows:

1. Structural components shall be evaluated in accordance with Tier 3 systematic evaluations procedure in Chapter 6. 2. Nonstructural components shall be evaluated in accordance with Chapter 13.

Exception: For general acute care hospitals, seismic evaluation shall be permitted to be in accordance with Chapter 6 of the California Administrative Code (CAC) when required by provisions of that chapter.

304A.3.5.2 ASCE 41-13 Section 2.4 Seismic Hazard. Modify ASCE 41-13 Section 2.4 with the following:

Response spectra and acceleration time histories shall be constructed in accordance with 2016 California Building Code (CBC) Sections 1613A, 1616A, and 1803A.6 or equivalent provision in later versions of the CBC.

304A.3.5.3 ASCE 41-13 Section 6.2. Modify ASCE 41-13 Section 6.2 with the following:

Data Collection Requirements. The extent of data collection shall be at Comprehensive level for all structures, including struc- tures upgraded to SPC-4D. A testing program for materials properties shall be approved by the enforcement agent prior to

3A-6 2025 CALIFORNIA EXISTING BUILDING CODE

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

PROVISIONS FOR ALL COMPLIANCE METHODS

commencement of material testing work. Previously approved material test results shall be permitted to be used to satisfy part of the comprehensive data collection requirements.

Exception: Data collection at Usual level shall be permitted for structures with SPC-2 or lower target performance objective.

Tension testing of reinforcing bars shall be in accordance with ASTM A615. All test specimens shall be the full section of the bar as rolled (8-in. gage length) and shall not be reduced.

At test sample locations, structural members, slabs and walls shall be repaired to a state that is equivalent to their original condition.

For buildings built under an OSHPD permit based on the 1976 or later edition of the CBC, where materials properties are shown on design drawings and original materials test data are available, no materials testing shall be required when approved by the enforcement agent.

304A.3.5.4 ASCE 41-13 Section 7.2.8.1. Modify ASCE 41-13 Section 7.2.8.1 with the following:

For the evaluation of one-story light-framed walls with or without hold-downs, ASCE 41-13 Equation 7-6 is permitted to be used. If Equation 7-6 is satisfied, no further evaluation or retrofit of the existing hold-down, if any, is required. If Equation 7-6 is not satisfied, hold-down shall be provided or retrofitted using ASCE 41-13 Equations 7-36 and 7-37. Equation 7-6 shall not be used to limit forces to other elements along the load path to the subject light-frame wall. Other elements, such as the diaphragm, collec- tor, shear wall, sill bolts, cripple wall, etc., shall be evaluated independently using ASCE 41-13 Equations 7-36 and 7-37 with the associated m or J factors listed under Chapter 12. Alternatively, if Equation 7-6 is not satisfied and retrofit is not performed, the wall contribution to the lateral resisting system shall be ignored. For all other building type conditions, Equation 7-6 shall not be used.

304A.3.5.5 ASCE 41-13 Section 7.3.2.1. Modify ASCE 41-13 Section 7.3.2.1 with the following:

Nonlinear Static Procedure. If higher mode effects are significant and building is taller than 75 feet above the base, the Nonlin- ear Dynamic Procedure shall be used.

304A.3.5.6 ASCE 41-13 Section 7.5.1. Modify ASCE 41-13 Section 7.5.1 with the following:

Acceptance Criteria – Drift Limitations. The interstory drift ratio shall not exceed the drift limits for Risk Category IV buildings in ASCE 7 Table 12.12-1 due to forces corresponding to BSE-1E or BSE-1N, as applicable.

Exception: Larger interstory drift ratios shall be permitted where justified by rational analysis that items identified in Chap- ter 6 Article 10 of the California Administrative Code can tolerate such drift and approved by the enforcement agent.

304A.3.5.7 ASCE 41-13 Section 7.5.1.4. Modify ASCE 41-13 Section 7.5.1.4 by the following:

Material Properties. Expected material properties are not permitted to be determined by multiplying lower bound values by the assumed factors specified in Chapters 8 through 12 and shall be based exclusively on materials tests.

304A.3.5.8 ASCE 41-13 Section 8.4. Modify ASCE 41-13 Section 8.4 with the following:

Foundation Strength and Stiffness. Foundation and soil strength shall be used to evaluate potential overturning, uplift and sliding for fixed base assumptions, and stiffness for flexible base assumptions, including deformations associated with those actions.

304A.3.5.9 ASCE 41-13 Section 8.4.1.1. Replace ASCE 41-13 Section 8.4.1.1 as follows:

Prescriptive Expected Capacities. Not permitted by OSHPD.

304A.3.5.10 ASCE 41-13 Section 8.4.2.3.2.1. Modify ASCE 41-13 Sections 8.4.2.3.2.1 and 8.4.2.3.2.2 as follows:

8.4.2.3.2.1 Alternatively, when seismic evaluation is performed for foundation after global analysis of the superstructure is complete, both overturning and axial seismic pseudo force demands are permitted to be divided by the m-factors above, provided the foundation is analyzed as a beam on Winkler springs (soil does not resist tension). The vertical spring stiffness values may be determined either from Figure 8-2 or Equation 8-11, or as provided by the geotechnical engineer. Acceptance criteria for soil bearing shall be considered met, based on one of the following methods, either A or B: A) Soil spring reactions are limited by the ultimate soil bearing capacity, and the foundation system is stable under the applied loads. B) The resisting soil pressure distribution under the footing is triangular such that the maximum soil bearing pressure at any point of the footing is less than the ultimate soil bearing capacity. Subject to the approval of the authority having jurisdiction, higher soil pressures may be permitted when appropri- ately justified.

The evaluation of the foundation structural element shall be considered as force controlled in accordance with the material chapters using the bearing pressure distribution under the footing from the same method used for the soil bearing acceptance criteria.

8.4.2.3.2.2 Alternatively, superstructure pseudo force overturning demands to the foundation are permitted to be divided by the appropriate m-factors above and applied to the mathematical model representing the foundation system only, re-analyzed as a beam on Winkler springs (soil does not resist tension). Acceptance criteria for soil bearing shall be considered met, based on one of the following methods, either A or B: A) Soil spring reactions are limited by the ultimate soil bearing capacity, and the foundation system is stable under the applied loads.

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

PROVISIONS FOR ALL COMPLIANCE METHODS

B) The resisting soil pressure distribution under the footing is triangular, and the maximum soil bearing pressure at any point of the footing is less than the ultimate soil bearing capacity. Subject to the approval of the authority having jurisdiction, higher soil pressures may be permitted when appropri- ately justified.

The evaluation of the foundation structural element shall be considered as force controlled in accordance with the material chapters using the bearing pressure distribution under the footing from the same method used for the soil bearing acceptance criteria.

304A.3.5.11 ASCE 41-13 Section 8.5.1. Modify ASCE 41-13 Section 8.5.1 with the following:

The product of RRS bsa x RRS e , shall not be less than 0.7.

The combined effect of kinematic interaction and foundation damping shall meet the following:

1. The site-specific response spectrum modified for soil-structure interaction effects shall not be taken as less than 80 percent of the spectral acceleration as determined from a site-specific response spectrum in accordance with ASCE 7 Section 21.3, or

2. The site-specific response spectrum modified for soil-structure interaction effects shall not be taken as less than 70 percent of the spectral acceleration as determined from the design response spectrum and MCE R response spectrum in accordance with ASCE 7 Sections 11.4.5 and 11.4.6, respectively.

Exception: For the seismic retrofit of existing nonconforming buildings, design ground motion shall be consistent with performance objectives in Section 304A.3.4.

304A.3.5.12 ASCE 41-13 Section 8.6. Modify ASCE 41-13 Section 8.6 with the following:

Seismic Earth Pressure. Where the grade difference from one side of the building to another exceeds one-half story height, the seismic increment of earth pressure shall be added to the gravity lateral earth pressure to evaluate the building overturning and sliding stability and the lateral force-resisting system below grade in combination with the building seismic forces.

304A.3.5.13 ASCE 41-13 Section 10.7.1.1. Modify ASCE 41-13 Section 10.7.1.1 with the following:

Monolithic Reinforced Concrete Shear Walls and Wall Segments. For nonlinear procedures, shear walls or wall segments with axial loads greater than 0.35 Po shall be included in the model as primary elements with appropriate strength and stiffness degrading properties assigned to those components subject to the approval of the enforcement agent. For linear procedures, the effects of deformation compatibility shall be investigated using moment-curvature section analyses and cyclic testing results of similar components to determine whether strengthening is necessary to maintain the gravity load-carrying capacity of that component.

Horizontal wall segments or spandrels reinforced similar to vertical wall segments or piers shall be classified as wall segments, not shear wall coupling beams, in Tables 10-19 through 10-22.

304A.3.5.14 ASCE 41-13 Section 10.12.3 Modify ASCE 41-13 Section 10.12.3 as follows:

Exception: Component actions that are deformation controlled are permitted to use their expected strengths for the accep- tance criteria.

304A.3.5.15 ASCE 41-13 Section 11.1. Modify ASCE 41-13 Section 11.1 by the following:

Scope: Unreinforced masonry walls (including unreinforced infill walls) and partitions are not permitted for General Acute Care (GAC) hospital buildings.

304A.3.5.16 ASCE 41-13 Section 14.1. Modify ASCE 41-13 Section 14.1 by the following:

Scope: For buildings located in Seismic Design Category F, verification of the interstory lateral displacements, the strength adequacy of the seismic force-resisting system and anchorage to the foundation shall be accomplished using the Nonlinear Dynamic Procedure.

304A.3.5.17 ASCE 41-13 Chapter 15 and 16. Not permitted by OSHPD.

304A.3.6 Modifications to ASCE 41-23. The text of ASCE 41-23 shall be modified as indicated in Sections 304A.3.6.1 through 304A.3.6.9.

304A.3.6.1 ASCE 41-23 Section 2.1. Modify ASCE 41-23 Section 2.1 with the following:

Seismic evaluations shall be performed for performance objective specified in Section 304A.3.4 of this code (CEBC) using proce- dure of this standard (ASCE 41-23) as follows:

1. Structural components shall be evaluated in accordance with Tier 3 systematic evaluations procedure in Chapter 6.

2. Nonstructural components shall be evaluated in accordance with Chapter 13.

Exception: For general acute care hospitals, seismic evaluation shall be permitted to be in accordance with Chapter 6 of the California Administrative Code (CAC) when required by provisions of that chapter.

304A.3.6.2 ASCE 41-23 Section 6.2. Modify ASCE 41-23 Section 6.2 with the following:

Data Collection Requirements. The extent of data collection shall be at Comprehensive level for all structures, including struc- tures upgraded to SPC-4D. A testing program for materials properties shall be approved by the enforcement agent prior to commencement of material testing work. Previously approved material test results shall be permitted to be used to satisfy part of the comprehensive data collection requirements.

extent of data collection shall be at Comprehensive level for all structures, including struc-_ tures upgraded to SPC-4D. A testing program for materials properties shall be approved by the enforcement agent prior to commencement of material testing work. Previously approved material test results shall be permitted to be used to satisfy part of the comprehensive data collection requirements.

3A-8 2025 CALIFORNIA EXISTING BUILDING CODE

on Jul 18, 2025 11:14 AM (CDT) THEREUNDER.

PROVISIONS FOR ALL COMPLIANCE METHODS

Tension testing of reinforcing bars shall be in accordance with ASTM A615. All test specimens shall be the full section of the bar as rolled (8-in. gage length) and shall not be reduced.

At test sample locations, structural members, slabs and walls shall be repaired to a state that is equivalent to their original condition.

For buildings built under an OSHPD permit based on the 1976 or later edition of the CBC, where materials properties are shown on design drawings and original materials test data are available, no materials testing shall be required when approved by the enforcement agent.

304A.3.6.3 ASCE 41-23 Section 7.2.9.1. Modify ASCE 41-23 Section 7.2.9.1 with the following:

For the evaluation of one-story light-framed walls with or without hold-downs, ASCE 41-23 Equation 7-6 is permitted to be used. If Equation 7-6 is satisfied, no further evaluation or retrofit of the existing hold-down, if any, is required. If Equation 7-6 is not satisfied, hold-down shall be provided or retrofitted using ASCE 41-23 Equations 7-39 and 7-40. Equation 7-6 shall not be used to limit forces to other elements along the load path to the subject light-frame wall. Other elements, such as the diaphragm, collector, shear wall, sill bolts, cripple wall, etc., shall be evaluated independently using ASCE 41-23 Equations 7-39 and 7-40 with the associated m or J factors listed under Chapter 12. Alternatively, if Equation 7-6 is not satisfied and retrofit is not performed, the wall contribution to the lateral resisting system shall be ignored. For all other building type conditions, Equation 7-6 shall not be used.

304A.3.6.4 ASCE 41-23 Section 7.5.1. Modify ASCE 41-23 Section 7.5.1 with the following:

Acceptance Criteria – Drift Limitations. The interstory drift ratio shall not exceed the drift limits for Risk Category IV buildings in ASCE 7 Table 12.12-1 due to forces corresponding to BSE-1E or BSE-1N, as applicable.

Exception: Larger interstory drift ratios shall be permitted where justified by rational analysis that both structural and nonstructural elements can tolerate such drift and approved by the enforcement agent.

304A.3.6.5 ASCE 41-23 Section 7.5.1.4. Modify ASCE 41-23 Section 7.5.1.4 by the following:

Material Properties. Expected material properties are not permitted to be determined by multiplying lower bound values by the assumed factors specified in Chapters 8 through 12.

304A.3.6.6 ASCE 41-23 Section 8.6.1. Modify ASCE 41-23 Section 8.6.1 with the following:

The product of RRS bsa x RRS e shall be not less than 0.7.

The combined effect of kinematic interaction and foundation damping shall meet the following: 1. The site-specific response spectrum modified for soil-structure interaction effects shall not be taken as less than 80 percent of the spectral acceleration as determined from a site-specific response spectrum in accordance with ASCE 7 Section 21.3; or

2. The site-specific response spectrum modified for soil-structure interaction effects shall not be taken as less than 70 percent of the spectral acceleration as determined from the design response spectrum and M CER response spectrum in accordance with ASCE 7 Sections 11.4.5 and 11.4.6, respectively.

Exception: For the seismic retrofit of existing nonconforming buildings, design ground motion shall be consistent with performance objectives in Section 304A.3.4 of this code.

304A.3.6.7 ASCE 41-23 Section 8.7. Modify ASCE 41-23 Section 8.7 with the following:

Seismic Earth Pressure. Where the grade difference from one side of the building to another exceeds one-half story height, the seismic increment of earth pressure shall be added to the gravity lateral earth pressure to evaluate the building overturning and sliding stability and the lateral force-resisting system below grade in combination with the building seismic forces.

304A.3.6.8 ASCE 41-23 Section 11.1. Modify ASCE 41-23 Section 11.1 by the following:

Scope: Unreinforced masonry walls (including unreinforced infill walls) and partitions are not permitted for General Acute Care (GAC) hospital buildings.

304A.3.6.9 ASCE 41-23 Chapter 16 and 17. Not permitted by OSHPD.