Section 3412A Compliance Alternatives for Additions, Alterations, Repairs and Seismic Retrofit to Existing Structures

Except for the modifications as set forth in Sections 3412A and 3413A 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. When load combinations which do not include seismic forces are required, the new building code provisions of this code shall be applicable.

Target building performance level shall be as follows:

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) as defined in Section 2.3.1.1 at Basic Safety Earthquake 1N (BSE-1N) Seismic Hazard Level; and
   2. Life Safety (LS) Structural performance level (S-3) as defined in Section 2.3.1.3 at Basic Safety Earthquake 2N (BSE-2N) Seismic Hazard Level;

   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 alterations or repairs of SPC-4D buildings shall be in accordance with Section 3412A.2.3.2 of this code.

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:

   1. Life Safety Structural Performance (S-3) Level as defined in ASCE 41 Section 2.3.1.3 at the Basic Safety Earthquake 1E (BSE-1E) Seismic Hazard Level; and
   2. Collapse Prevention (CP) building performance level (5-D) in accordance with 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 Section 2.3.2.2 at BSE-1E Seismic Hazard Level.

3. All other hospital buildings:

   1. Operational Building Performance Level of (1-A) as defined in Section 2.3.3.1 at Basic Safety Earthquake 1N (BSE-1N) Seismic Hazard Level;
   2. Life Safety (LS) building performance level (S-3) as defined in Section 2.3.1.3 at Basic Safety Earthquake 2N (BSE-2N) Seismic Hazard Level.

Use of material properties based on historical information as default values shall not be permitted.

The selection of a particular analysis procedure from ASCE 41 shall be subject to the approval of the enforcement agency.

Prior to implementation of ASCE 41 Nonlinear Dynamic Procedure, the ground motion, analysis and design methods, material assumptions and acceptance criteria proposed by the engineer shall be reviewed by the enforcement agency.

Where analysis/modeling parameters or acceptance criteria for structural elements are not provided in ASCE 41 or are considered to be inadequate, the analysis/modeling parameters or acceptance criteria shall be permitted to be established on the basis of test, using a criteria acceptable to the building official, and ASCE 41 Section 7.6.3.

Construction, testing, inspection and structural observation requirements shall be as required for new construction.

Not withstanding 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 this section. When load combinations that do not include seismic forces are required, the new building provisions of this code shall be applicable.

New hospitals (facility) or new building(s), larger than 4000 sq ft, designed and built to the requirements of this code for general acute care hospital buildings shall be considered to satisfy the requirements of SPC 5 and NPC 5.

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 Section 2.3.1.1 of ASCE 41 at BSE-1N;
2. Life Safety performance level S-3 in accordance with Section 2.3.1.3 of ASCE 41 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 Section 2.3.2.1 of ASCE 41 at BSE-1N.

Nonconforming hospital buildings satisfying the following requirements and one of Sections 3412A.2.3.1, 3412A.2.3.2 or 3412A.2.3.3, 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 3413A.1.3 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.

Nonconforming buildings shall satisfy the following requirements:

1. The California Building Code, 1980 (CBC 1980), as used in this chapter, consists of the Uniform Building Code, 1979 (UBC 1979) along with requirements contained in:

   1. California Code of Regulations, Title 24-Building Standards, dated February 2, 1980 (Revision record for Register 80, No. 5).
   2. California Code of Regulations, Title 22 – Social Security, dated October 13, 1979 (Revision Record for Register 79, No 41).
   3. California Code of Regulations, Title 17 – Public Health, dated October 13, 1979 (Revision Record for Register 79, No 41-B).
2. All existing structural elements of Seismic Force Resisting System (SFRS) shall satisfy the detailing requirements in the CBC 1980 or demonstrate that the level of seismic performance is equivalent to that given in the CBC 1980, as determined by the building official.
3. A continuous load path or paths with adequate strength and stiffness to transfer all the forces from the point of origin to final point of resistance shall be justified by analysis.
4. Site data report in accordance with the CBC 1980 shall establish that seismically induced differential settlement does not exceed 1” in 40’.
5. Adjacent buildings shall satisfy the SPC building separation requirements in accordance with the California Administrative Code, Chapter 6 Section 3.4.

6. The addition of new structural elements or strengthening of existing structural elements for retrofit of nonconforming buildings to SPC-4D shall comply with the following:

   1. The seismic demand (forces or displacements) shall be in accordance with the CBC 1980;
   2. Capacity, detailing and connections for new structural elements shall satisfy the requirements in this code (CBC 2016) for new construction; and
   3. The strengthening of existing structural elements shall use capacities determined in accordance with this code (CBC 2016) for new construction consistent with the detailing and connections used in the strengthened member.
7. All construction, quality assurance and quality control shall be in accordance with the new construction provisions of this code (CBC 2016).
8. Elements not part of the Seismic Force Resisting System (SFRS), including those identified in the California Administrative Code Chapter 6, Article 10, shall be evaluated using seismic forces and the requirements of the CBC 1980.

9. Any column or wall that forms part of two or more intersecting SFRS and is subjected to axial load due to seismic forces acting along either principal plan axis equaling or exceeding 20 percent of the axial design strength of the column or wall shall be evaluated for the most critical load effect due to application of seismic force in any direction. The most critical load effect may be deemed to be satisfied if members and their foundations are evaluated for 100 percent of the forces for one direction plus 30 percent of the forces for the perpendicular direction, whereby the combination produces the maximum effect.

   Exceptions: The following buildings (with structural irregularities or unusual configuration/system) shall not be eligible for the SPC-4D upgrade using the prescriptive provisions in this section:

   1. Buildings with prohibited irregularities in accordance with Section 1616A.1.10 of this code.
   2. Buildings taller than 5-stories or 65' height above the base having horizontal or vertical irregularities in accordance with ASCE 7 Tables 12.3-1 Items # 1a, 1b and 3 or 12.3-2 Items #1a, 1b, 5a and 5b.
   3. Buildings with unusual configuration or structural system, as determined by the building official.

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 are satisfied:

1. Damage control structural performance level (S-2) in accordance with Section 2.3.1.2.1 of ASCE 41 at BSE-1E; and
2. Collapse Prevention Structural Performance Level (S-5) in accordance with Section 2.3.1.5 of ASCE 41 at BSE-2E; and
3. Items identified in Chapter 6, Article 10 of the California Administrative Code satisfy the requirements of Position Retention nonstructural performance level (N-B) in accordance with Section 2.3.2.2 at BSE-1E.

Structures satisfying the requirements of this code for new general acute care hospital buildings design shall be deemed to satisfy the SPC-4D requirements of Table 2.5.3, Chapter 6 of the California Administrative Code.

All existing structural elements of Seismic Force Resisting System (SFRS) shall satisfy the detailing requirements of this code for new construction or demonstrate that the level of seismic performance is equivalent, as determined by the building official. A demonstration of equivalence shall consider the regularity, overstrength, redundancy, and ductility of the structure.

Elements not part of the Seismic Force Resisting System (SFRS), including those identified in the California Administrative Code Chapter 6, Article 10, shall be evaluated using seismic forces and the requirements of this code for new general acute care hospital buildings.

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 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 at BSE-1E.

A continuous load path of sufficient strength and stiffness between the component and the supporting structure shall be verified. Local elements of the supporting structure shall be verified for the component loads where they control the design of the elements or their connections.

Nonstructural components for Operational Nonstructural performance level (N-A) in Section 2.3.2.1 or NPC-4 shall satisfy the requirements of this code for new construction. Nonstructural components for NPC-5 shall satisfy Operational performance level N-A/NPC-4 and Section 1616A.1.40 Items 1 & 2 of this code.

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

Exceptions:

1. Evaluation procedure of Article 11, Chapter 6, of the California Administrative Code shall be used for seismic evaluation of NPC 2, NPC 3/NPC 3R, NPC 4 and NPC 5, where specific procedure is not outlined in ASCE 41. Administrative and permitting provisions outlined in Article 11, Chapter 6, of the California Administrative Code shall apply.
2. Supports and attachments of nonstructural components, except those listed in Item 4 below, in buildings in seismic performance categories SPC 1 and SPC 2 with a performance level of NPC 3R shall be permitted to comply with the provisions of Section 1630A of the 1995 California Building Code using an importance factor I_p =1.0. The capacity of welds, anchors and fasteners shall be determined in accordance with requirements of this code.
3. Supports and attachments of nonstructural components, except those listed in Item 4 below, in buildings in seismic performance categories SPC 1 or SPC 2 with a performance level of NPC 3 or higher, and SPC 3, SPC 4 or SPC-4D, shall be permitted to comply with the provisions of Section 1630B of the 1998 California Building Code using an importance factor I_p =1.5. The capacity of welds, anchors and fasteners shall be determined in accordance with requirements of this code.
4. Supports and attachments for systems listed under NPC-2 and NPC-5 (excluding those specifically listed for NPC-3/NPC-3R and NPC-4) in the California Administrative Code, Chapter 6, Table 11.1 shall satisfy the requirements of this code for new construction and Items 2 and 3 above shall not be applicable.

5. For NPC 3R, the adequacy of load path for nonstructural elements need only be verified when the total reaction at the point of support (including the application of F_p) exceeds the following limits:

   1. 250 pounds for components or equipment attached to light frame walls. For the purposes of this requirement, the sum of the absolute value of all reactions due to component loads on a single stud shall not exceed 250 pounds.
   2. 1,000 pounds for components or equipment attached to roofs, or walls of reinforced concrete or masonry construction.

   3. 2,000 pounds for components or equipment attached to floors or slabs-on-grade.

      Exception: If the anchorage or bracing is configured in a manner that results in significant torsion on a supporting structural element, the effects of the nonstructural reaction force on the structural element shall be considered in the anchorage design.