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ORDINANCE 1538 ORDINANCE NO. 1538 AN ORDINANCE ADOPTING APPENDIX V (VOLUNTARY SEISMIC RETROFIT); VOLUNTARY PRESCRIPTIVE PROVISIONS FOR SEISMIC STRENGTHENING OF CRIPPLE WALLS AND SILL PLATE ANCHORAGE OF LIGHT, WOOD- FRAME RESIDENTIAL BUILDINGS; VOLUNTARY EARTHQUAKE RISK REDUCTION IN WOOD-FRAME RESIDENTIAL BUILDINGS WITH SOFT,WEAK OR OPEN FRONT WALLS; AND VOLUNTARY EARTHQUAKE HAZARD REDUCTION IN EXISTING CONCRETE BUILDINGS; AND AMENDING THE EL SEGUNDO MUNICIPAL CODE TO REFLECT SUCH ADOPTION AND TO RE-NUMBER TITLE 13, CHAPTER 9 (EARTHQUAKE HAZARD REDUCTION IN EXISTING BUILDINGS) The City Council of the city of El Segundo does ordain as follows: SECTION 1: Findings. The City Council finds and declares as follows: A. The City may adopt model codes by reference pursuant to Government Code §§ 50022.2, et seq.; B. Health and Safety Code § 17958 requires the City to adopt certain codes that are set forth in Health and Safety Code § 17922 and published in the California Code of Regulations; C. Additional amendments have been made to Codes are found to be either administrative or procedural in nature or concern themselves with subjects not covered in such Codes. The changes made include provisions making each of said Codes compatible with other Codes enforced by the City; D. El Segundo Municipal Code Title 13 Chapter 9 contains provisions for earthquake hazard reduction in existing unreinforced masonry bearing wall buildings constructed prior to 1934. It is in the public interest to adopt Earthquake Hazard Reduction regulations for other types of buildings as set forth in this Ordinance; E. Notice of public hearing to consider the adoption of the codes was published pursuant to Government Code § 6066 and a duly noticed public hearing was held on December 6, 2016, regarding the adoption of the Codes; F. Pursuant to § 50022.6 of the Government Code, at least one copy of all codes adopted by reference were filed with the City Clerk of the City and were available for public inspection for at least fifteen (15) days preceding the date of the hearing; ORDINANCE No. 1538 Page 2 of 10 G. In 1990, the City Council adopted Ordinance No. 1152, which adopted standards relating to Earthquake Hazard Reduction in Existing Buildings; and H. The City Council desires to re-number the existing Earthquake Hazard Reduction in Existing Buildings chapter, in its entirety, so that it now appears in Title 13, Chapter 18 of the El Segundo Municipal Code. SECTION 2: Title 13, Chapter 9 of the El Segundo Municipal Code ("ESMC") is hereby re-numbered as Title 13, Chapter 18, to read as follows: "CHAPTER 18 EARTHQUAKE HAZARD REDUCTION IN EXISTING BUILDINGS § 13-18-1: PURPOSE § 13-18-2: SCOPE § 13-18-3: DEFINITIONS § 13-18-4: RATING CLASSIFICATIONS § 13-18-5: GENERAL REQUIREMENTS § 13-18-6: ADMINISTRATION § 13-18-7: ANALYSIS AND DESIGN § 13-18-8: MATERIALS OF CONSTRUCTION § 13-18-9: INFORMATION REQUIRED ON PLAN § 13-18-10: TABLES" SECTION 3: Title 13, Chapter 18 of the ESMC is amended to read as follows: "Section 13-18-11. ADOPTION OF APPENDIX V: VOLUNTARY SEISMIC RETROFIT § 13-18-V100: VOLUNTARY EARTHQUAKE HAZARD REDUCTION IN EXISTING REINFORCED CONCRETE AND REINFORCED MASONRY WALL BUILDINGS WITH FLEXIBLE DIAPHRAGMS § 13-18-V101: PURPOSE The purpose of this Chapter is to promote public safety and welfare by reducing the risk of death or injury that may result from the effects of earthquakes on reinforced concrete and masonry wall buildings with flexible diaphragms designed under the building codes in effect before January 1, 1995. These buildings are potentially hazardous and prone to significant damage, including possible collapse, in a moderate to major earthquake. These structures typically shelter large numbers of persons and property for retail, food markets, food distribution centers, warehousing, aerospace, industrial/manufacturing and general business and office use. Their continued use after an earthquake is also essential to the local economy and its post-earthquake recovery. ORDINANCE No. 1538 Page 3of10 The provisions of this Chapter are minimum standards for structural seismic resistance established primarily to reduce the risk of loss of life or injury on both subject and adjacent properties and will not necessarily prevent all earthquake damage to an existing building which complies with these standards. This Chapter cannot require existing electrical, plumbing, mechanical or fire safety systems to be altered unless they constitute a hazard to life or property. This Chapter provides voluntary retrofit standards for deficient wall anchorage systems on structures that are not subject to the mandatory provisions of Chapter When fully followed, these standards will strengthen the portion of the structure that is most vulnerable to earthquake damage. § 13-184102: SCOPE The voluntary provisions of this Chapter apply to existing buildings of the following types: 1. Cast-in-place reinforced concrete or masonry wall buildings with flexible diaphragms designed under building codes in effect before January 1, 1995. 2. Tilt-up concrete wall buildings with flexible diaphragms designed under the building codes in effect before January 1, 1995, but after January 1, 1976. All existing reinforced masonry or concrete buildings with flexible diaphragms, including tilt-up concrete wall buildings, designed under the Building Code in effect on or after January 1, 1995, must be designed in conformance with Chapter 16 of the CBC. § 13-184103: DEFINITIONS For the purposes of this Chapter, the applicable definitions in Chapter 2, Chapter 16, Chapter 19 and Chapter 23 of this Code; Chapter 1, Chapter 3, Chapter 4, Chapter 5, Chapter 6 and Chapter 11 of ASCE 7, and the following apply: ANCHORAGE SYSTEM is the system of all structural elements and connections, which support the concrete or masonry wall in the lateral direction, including diaphragms and subdiaphragms, wall anchorage and continuity or cross tie connectors in subdiaphragms and main diaphragms. COMMENCED CONSTRUCTION is construction pursuant to a valid building permit that has progressed to the point that one of the called inspections as required by the Department has been made and the work for which the inspection has been called has been judged by the Department to be substantial and has been approved by the Department. EXISTING BUILDING is an erected building for which a legal building permit and a certificate of occupancy have been issued. ORDINANCE No. 1538 Page 4 of 10 FLEXIBLE DIAPHRAGM is any diaphragm constructed of wood structural panel, diagonal or straight wood sheathing, metal decking without a structural concrete topping, or horizontal rod bracing. HISTORICAL BUILDING is any building designated or currently in the process of being designated as a historical building by an appropriate federal, state or City jurisdiction. REINFORCED CONCRETE WALL is a concrete wall that has 50 percent or more of the reinforcing steel required for reinforced concrete in Chapter 19. REINFORCED MASONRY WALL is a masonry wall that has 50 percent or more of the reinforcing steel required by Chapter 21. RETROFIT is strengthening or structurally improving the lateral force resisting system of an existing building by alteration of existing or addition of new structural elements. TILT-UP CONCRETE WALL is a form of precast concrete panel construction either cast in the horizontal position at the site and after curing, lifted and moved into place in a vertical position, or cast off-site in a fabricator's shop. § 13-184104: ANALYSIS AND DESIGN V104.1. Wall Panel Anchorage. Concrete and masonry walls must be anchored to all floors and roofs which provide lateral support for the wall. The anchorage must provide a positive direct connection between the wall and floor or roof construction capable of resisting a horizontal force equal to 30 percent of the tributary wall weight for all buildings, and 45 percent of the tributary wall weight for essential buildings, or a minimum force of 250 pounds per linear foot of wall, whichever is greater. The required anchorage must be based on the tributary wall panel assuming simple supports at floors and roof. EXCEPTION: An alternate design may be approved by the Building Official when justified by well- established principles of mechanics. V104.2. Special Requirements for Wall Anchors and Continuity Ties.The steel elements of the wall anchorage systems and continuity ties must be designed by the allowable stress design method using a load factor of 1.7. The 1/3 stress increase permitted by Chapter 16 cannot be permitted for materials using allowable stress design methods. The strength design specified in Chapter 19 using a load factor of 2.0 in lieu of 1.4 for earthquake loading, must be used for the design of embedment in concrete. Wall anchors must be provided to resist out-of- plane forces, independent of existing shear anchors. ORDINANCE No. 1538 Page 5 of 10 EXCEPTION: Existing cast-in-place shear anchors may be used as wall anchors if the tie element can be readily attached to the anchors and if the engineer or architect can establish tension values for the existing anchors through the use of approved as-built plans or testing, and through analysis showing that the bolts are capable of resisting the total shear load while being acted upon by the maximum tension force due to seismic loading. Criteria for analysis and testing must be determined by the Building Official. Expansion anchors are not allowed without special approval of the Building Official. Attaching the edge of plywood sheathing to steel ledgers is not considered as complying with the positive anchoring requirements of the Code; and attaching the edge of steel decks to steel ledgers is not considered as providing the positive anchorage of this Code unless testing and analysis are performed, which establish shear values for the attachment perpendicular to the edge of the deck. V104.3. Development of Anchor Loads into the Diaphragm. Development of anchor loads into roof and floor diaphragms must comply with Chapter 12 of ASCE 7. EXCEPTION: If continuously tied girders are present, then the maximum spacing of the continuity ties is the greater of the girder spacing or 24 feet (7315 mm). In wood diaphragms, anchorage cannot be accomplished by use of toe nails or nails subject to withdrawal, nor must wood ledgers, top plates or framing be used in cross-grain bending or cross-grain tension. The continuous ties required by Chapter 12 of ASCE 7 must be in addition to the diaphragm sheathing. Lengths of development of anchor loads in wood diaphragms must be based on existing field nailing of the sheathing unless existing edge nailing is positively identified on the original construction plans or at the site. At reentrant corners, continuity collectors may be required for existing return walls not designed as shear walls, to develop into the diaphragm a force equal to the lesser of the rocking or shear capacity of the return wall, or the tributary shear but not exceeding the capacity of the diaphragm. Shear anchors for the return wall must be commensurate with the collector force. If a truss or beam other than rafters or purlins is supported by the return wall or by a column integral with the return wall, an independent secondary column is required to support the roof or floor members whenever rocking or shear capacity of the return wall is governing. V104.4. Anchorage at Pilasters. Anchorage of pilasters must be designed for the tributary wall anchoring load per Section V104.1 of this Code, considering the wall as a two-way slab. The edge of the two-way slab must be considered "fixed" when there is continuity at pilasters, and considered "pinned" at roof or floor levels. The pilasters or the walls immediately adjacent to the pilasters must be anchored directly to the roof framing such that the existing vertical anchor bolts at the top of the pilasters are by-passed without causing tension or shear failure at the top of the pilasters. ORDINANCE No. 1538 Page 6 of 10 EXCEPTION: If existing vertical anchor bolts at the top of the pilasters are used for the anchorage, then additional exterior confinement must be provided. The minimum anchorage at a floor or roof between the pilasters must be that specified in Section V104.1 of this Code. V104.5. Symmetry. Symmetry of connectors in the anchorage system is required. Eccentricity may be allowed when it can be shown that all components of forces are positively resisted and justified by calculations or tests. V104.6. Minimum Roof Member Size. Wood members used to develop anchorage forces to the diaphragm must be of minimum nominal width for new construction and replacement. All such members must be designed for gravity and earthquake forces as part of the wall anchorage system. For existing structural members, the allowable stresses must be without the 1/3 stress increase per Section V104.2. V104.7. Combination of Anchor Types. To repair and retrofit existing buildings, a combination of different anchor types of different behavior or stiffness is prohibited. The capacity of the new and existing connectors cannot be added. V104.8. Prohibited Anchors. Usage of connectors that were bent or stretched from the intended use is prohibited. V104.9: Crack and Damage Repairs, Evaluation of Existing Structural Alterations. The engineer or architect must report any observed structural conditions and structural damage that have imminent life safety effects on the buildings and recommend repairs. This includes alterations such as openings cut in existing wall panels without a building permit. Evaluations and repairs must be reviewed and approved by the Building Official. V104.10. Miscellaneous. Existing mezzanines relying on the concrete or masonry walls for vertical or lateral support must be anchored to the walls for the tributary mezzanine load. Walls depending on the mezzanine for lateral support must be anchored per Sections V104.1, V104.2 and V104.3 of this Code. EXCEPTION: Existing mezzanines that have independent lateral and vertical support need not be anchored to the concrete or masonry walls. Existing interior masonry or concrete walls not designed as shear walls, which extend to the floor above or to the roof diaphragm must also be anchored for out-of-plane forces per Section V104.1, V104.2 and V104.3 of this Code. In the in-plane direction, the walls may be isolated or must be developed into the diaphragm for a lateral force equal to the lesser of the rocking or shear capacity of the wall, or the tributary shear but not exceeding the diaphragm capacity. ORDINANCE No. 1538 Page 7 of 10 V104.11. Historical Buildings. Qualified historical buildings must be permitted to use alternate building standards or deviations from this Chapter in order to preserve their original or restored architectural elements and features. § 13-184105: MATERIALS OF CONSTRUCTION. All materials permitted by this Code. § 13-184106: INFORMATION REQUIRED ON PLANS, V106.1. General. In addition to the seismic analysis required elsewhere in this Chapter, the licensed engineer or architect responsible for the seismic analysis of the building must record the information required by this section on the approved plans. V106.2. Information Required. The plans must accurately reflect the results of the engineering investigation and design and show all pertinent dimensions and sizes for plan review and construction. The following must be provided: 1. Floor plans and roof plans must show the existing framing construction, diaphragm construction, proposed wall anchors, cross-ties and collectors. Existing nailing, anchors, ties and collectors must also be shown on the plans if these are part of the design, and these structural elements need to be verified in the field. 2. At elevations where there is alterations or damage, the details must show the roof and floor heights, dimensions of openings, location and extent of existing damage, and proposed repair. 3. Typical concrete or masonry wall sections with wall thickness, height, and location of anchors must be provided. 4. Details must include the existing and new anchors and the method of development of anchor forces into the diaphragm framing; existing and new cross- ties, existing and new or improved support of the roof and floor girders at pilasters or walls. V106.3. Engineer's or Architect's Statement. The responsible engineer or architect must state on the approved plans, the following: 1. "1 am responsible for this building's seismic strengthening design of the tilt-up concrete wall anchorage system in compliance with the minimum seismic resistance standards of Chapter V1 of the California Building Code, as adopted by the El Segundo Municipal Code." or when applicable: 2. "The Registered Deputy Inspector, required as a condition of the use of structural design stresses requiring continuous inspection, will be responsible to me, the California Licensed Engineer or Architect, as required by Section 1704 of the California Building Code, as adopted by the El Segundo Municipal Code." § 13-184107: REQUIRED BUILDING MAINTENANCE. ORDINANCE No. 1538 Page 8 of 10 Every building within the scope of this Chapter which has been analyzed to demonstrate compliance or structurally altered to comply with the minimum earthquake standards in this Chapter must be maintained in conformity with the requirements of this Chapter in effect at the time of such analysis or structural alteration. TABLE NO. V1-A RATING CLASSIFICATIONS Classification Occupant Load Essential N/A Group 1 300 or more Group II 100 to 299 Group 111 50 to 99 Group IV Less than 50 Section 13-18-12. ADOPTION OF VOLUNTARY PRESCRIPTIVE PROVISIONS FOR SEISMIC STRENGTHENING OF CRIPPLE WALLS AND SILL PLATE ANCHORAGE OF LIGHT, WOOD-FRAME RESIDENTIAL BUILDINGS § 13-18-V200: VOLUNTARY PRESCRIPTIVE PROVISIONS FOR SEISMIC STRENGTHENING OF CRIPPLE WALLS AND SILL PLATE ANCHORAGE OF LIGHT, WOOD-FRAME RESIDENTIAL BUILDINGS. Pursuant to California Government Code § 50022.1 to 50022.8, Chapter A3 of the California Existing Building Code ("CEBC"), 2016 Edition, published at Title 24, Part 10, of the California Code of Regulations, is adopted by reference, subject to the amendments, additions and deletions set forth below. One true copy of the CEBC, is on file in the office of the Building Official and is available for public inspection as required by law." Section 13-18-13. ADOPTION OF VOLUNTARY EARTHQUAKE RISK REDUCTION IN WOOD-FRAME RESIDENTIAL BUILDINGS WITH SOFT, WEAK OR OPEN FRONT WALLS. § 13-18-V300: VOLUNTARY EARTHQUAKE RISK REDUCTION IN WOOD- FRAME RESIDENTIAL BUILDINGS WITH SOFT, WEAK OR OPEN FRONT WALLS. Pursuant to California Government Code § 50022.1 to 50022.8, Chapter A4 of the California Existing Building Code ("CEBC"), 2016 Edition, published at Title 24, Part 10, of the California Code of Regulations, is adopted by reference, subject to the amendments, additions and deletions set forth below. One true copy of the CEBC, is on file in the office of the Building Official and is available for public inspection as required by law." Section 13-18-14. ADOPTION OF VOLUNTARY EARTHQUAKE HAZARD ORDINANCE No. 1538 Page 9 of 10 REDUCTION IN EXISTING CONCRETE BUILDINGS. § 13-18-V400: VOLUNTARY EARTHQUAKE HAZARD REDUCTION IN EXISTING CONCRETE BUILDINGS. Pursuant to California Government Code § 50022.1 to 50022.8, Chapter A5 of the International Existing Building Code ("IEBC"), 2015 Edition, published by the International Code Council, is adopted by reference, subject to the amendments, additions and deletions set forth below. Sections A502 through A507 are amended as follows: All references to "International Building Code" shall be amended to read "2016 California Building Code ("CBC") as amended by the El Segundo Municipal Code". One true copy of the IEBC, is on file in the office of the Building Official and is available for public inspection as required by law." SECTION 4: Environmental Assessment. The City Council determines that this ordinance is exempt from review under the California Environmental Quality Act (California Public Resources Code §§ 21000, et seq., "CEQA") and the regulations promulgated thereunder (14 California Code of Regulations §§ 15000, et seq., the "CEQA Guidelines") because it consists only of minor revisions and clarifications to an existing code of construction-related-regulations and specification of procedures related thereto and will not have the effect of deleting or substantially changing any regulatory standards or findings required therefor, and therefore does not have the potential to cause significant effects on the environment. In addition, this ordinance is an action being taken for enhanced protection of the environment and is exempt from further review under CEQA Guidelines § 15308. SECTION 5: Construction. This Ordinance must be broadly construed in order to achieve the purposes stated in this Ordinance. It is the City Council's intent that the provisions of this Ordinance be interpreted or implemented by the City and others in a manner that facilitates the purposes set forth in this Ordinance. SECTION 6: Savings Clause. Repeal of any provision of the ESMC or any other city ordinance herein will not affect any penalty, forfeiture, or liability incurred before, or preclude prosecution and imposition of penalties for any violation occurring before, this Ordinance's effective date. Any such repealed part will remain in full force and effect for sustaining action or prosecuting violations occurring before the effective date of this Ordinance. SECTION 7: Severability. If any part of this Ordinance or its application is deemed invalid by a court of competent jurisdiction, the city council intends that such invalidity will not affect the effectiveness of the remaining provisions or applications and, to this end, the provisions of this Ordinance are severable. SECTION 8: Validity of Prior Code Sections. If this the entire Ordinance or its application is deemed invalid by a court of competent jurisdiction, any repeal of the ESMC or other the city ordinance by this Ordinance will be rendered void and cause such ESMC provision or other the city ordinance to remain in full force and effect for all purposes. ORDINANCE No. 1538 Page 10 of 10 SECTION 9: Publication. The City Clerk is directed to certify the passage and adoption of this Ordinance; cause it to be entered into the City of El Segundo's book of original ordinances; make a note of the passage and adoption in the records of this meeting; and, within fifteen (15) days after the passage and adoption of this Ordinance, cause it to be published or posted in accordance with California law. SECTION 10: Effective Date. This Ordinance will become effective on the 31st day following its passage and adoption. SECTION 11: Filing with Building Standards Commission. The City Clerk must file a certified copy of this Ordinance with the California Building Standards Commission. PASSED, APPROVED, AND ADOPTED ORDINANCE No. 1538 on this 6th day of December, 2016. uz . e Fuentes, Mayor APPROVED AS TO FORM Mark . Hensley, C ty ttorney ATTEST: STATE OF CALIFORNIA ) COUNTY OF LOS ANGELES ) SS CITY OF EL SEGUNDO ) I, Tracy Weaver, City Clerk of the City of El Segundo, California, do hereby certify that the whole number of members of the City Council of said City is five; that the foregoing Ordinance No. 1538 was duly introduced by said City Council at a regular meeting held on the 1 st day of November, 2016, and was duly passed and adopted by said City Council, approved and signed by the Mayor, and attested to by the City Clerk, all at a regular meeting of said Council held on the 6th day of December, 2016, and the same was so passed and adopted by the following vote: AYES: Mayor Fuentes, Mayor Pro Tern Boyles, Council Member Dugan and Council Member Pirsztuk NOES: None ABSENT: Council Member Brann ABSTAIN: None Tr y Wa aver, City Clerk , ,...,. d