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Ordinance No. 853471 ORDINANCE NO. 853 AN ORDINANCE OF THE CITY COUNCIL OF THE CITY OF CYPRESS AMENDING CHAPTER 5, "BUILDINGS" OF THE CODE OF THE CITY OF CYPRESS BY THE ADDITION OF SECTION 5 -2(A) (19) WHICH MODIFIES THE 1988 EDITION OF THE UNIFORM BUILDING CODE, AS ADOPTED BY SAID CITY, BY ADDING CHAPTER 71, FOR THE PURPOSES OF THE IDENTIFICATION OF SEISMIC HAZARDS AND THE MITIGATION THEREOF AS REQUIRED BY GOVERNMENT CODE 8875 ET SEQ. WHEREAS, Cypress, like most California Cities is subject to periodic earthquakes; and, WHEREAS, SB 547, now codified as Government Code Section 8875 et seq., enacted by the State of California in 1986 requires that all cities within Seismic Zone 4 to identify all potentially hazardous buildings and to establish a program for mitigation of identified potentially hazardous buildings; and, WHEREAS, In the City of Cypress there are several unreinforced masonry structures which may be subject to SB 547. NOW, THEREFORE, THE CITY COUNCIL OF THE CITY OF CYPRESS DOES ORDAIN AS FOLLOWS: SECTION I. Chapter 5, "Buildings ", Section 5 -2, of the Code of the City of Cypress is hereby amended by the addition of a new subsection (19) as further amendments to the 1988 edition of the Uniform Building Code to read as follows: Section 5- 2(A)(19) Chapter 71 is hereby added to read as follows: "Chapter 71 SEISMIC HAZARDS IDENTIFICATION PROGRAM Sections 71.01 - 71.09 71.01 Purpose 71.02 Definitions 71.03 Potentially Hazardous Buildings 71.04 Exemptions 71.05 Identification Process 71.06 Final Listing of Potentially Hazardous Buildings 71.07 Order and Recordation 71.08 Appeal from Order 71.09 Engineering Reports 71.10 Responsibilities of Building Owners 71.11 Status Reports 71.12 Abatement of Dangerous Buildings 71.13 Remedies 71.01 Purpose The purpose of this Section is to promote public safety by identifying those potentially hazardous buildings in Cypress and establish a program to mitigate potential hazards as required by SB 547, Government Code Section 8875 et seq. 71.02 Definitions. (a) "Bearing wall" means any wall supporting a floor or roof where the total superimposed load exceed one hundred (100) pounds per linear foot, or any unreinforced masonry wall supporting its own weight when over six (6) feet in height. (b) "Building," for the purpose of determining occupant load, means any contiguous or interconnected structure; for purposes of engineering evaluation, means the entire structure or a portion thereof which will respond to seismic forces as unit. -1- 472 (c) "Building Geometry" means a building's shape or configuration, including setbacks or wall /column lines, reentrant corners, discontinuities in vertical and horizontal lateral force diaphragms, open storefront and building stiffness variations due to the distribution of resisting elements or the use of material of differing properties within the same structural element, or other irregularities in plan or elevation. (d) "Capacity for transfer" means the maximum allowable capacity of a structural system or connection to resist in a ductile manner the lateral forces it would encounter due to earthquake forces. (e) "Civil Engineer or Structural Engineer" means an active, licensed civil or structural engineer registered by the State of California pursuant to the rules and regulations of Title 16, Chapter 5 of the California Code of Regulations. (f) "External hazard" means an object attached to or forming the exterior facade of a building which may fall onto pedestrians or occupants of adjacent buildings. Examples of this type of hazard include, but are not limited to, the following: 1. Nonstructural exterior wall panels, such as masonry infill or decorative precast concrete. 2. Parapets. 3. Marquees, awnings or other roof -like projections from a building. 4. Masonry or stone wall veneer and wall ornamentation, including cornices or other decorative appendages. 5. Masonry chimneys. 6. Tile roofing. 7. Wall signs and exterior lighting fixtures hung from a building exterior. 8. Fire escapes or balconies. (g) "Occupants" means the total occupant load of a building determined by Table 33 -A of the 1988 Uniform Building Code of the actual maximum number of occupants in that building if that number is less than seventy five percent (75 %) of the number determined by using Table 33 -A. The number of actual occupants may be documented by counting actual seating capacity if permanent seating is provided in occupancy, or by employee and client counts which can be substantiated as a practical maximum use of the space in the building. The Building Official will establish the procedure for documenting occupant loads. (h) "Solution" means any justifiable method that will provide for the transfer of lateral forces through a system or connection to a degree which will substantially eliminate a potential collapse failure. A general description of the methods and materials to be used shall be included in sufficient detail to allow for a cost estimate of the solution to be made (i. e. , adding shear walls, overlaying horizontal diaphragms, strengthening critical connections, etc.). -2- 473 (i) "Unreinforced masonry (URM)" building means any building containing walls constructed wholly or partially with any of the following materials: 1. Unreinforced brick masonry. 2. Unreinforced concrete masonry. 3. Hollow clay tile. 4. Adobe or unburned clay masonry. Unreinforced refers to construction without imbedded metal rebar of 3/8" diameter minimum or wire mesh meeting engineering standards for the specific building type in question. (j) "Unreinforced masonry (URM) wall" is a masonry wall in which the area of reinforcing steel is less than twenty five percent (25 %) of that required by the Building Code for reinforced masonry. (k) "Unreinforced masonry bearing wall" is a URM wall which provides the vertical support for a floor or roof for which the total superimposed load is over one hundred (100) pounds per linear foot of wall. 71.03 Potentially Hazardous Buildings The provisions of this Chapter shall apply to all existing buildings in Seismic Zones 3 and 4 having at least one unreinforced masonry bearing wall. Except as provided herein, all other provisions of the Building Code shall apply. 71.04 Exemptions This Chapter shall not apply to: 1. Detached one or two family dwellings and detached apartment houses containing less than 5 dwelling units and used solely for residential purposes. 2. Essential Facilities as defined in Table 23 -K of the Building Code. 3. Hazardous Facilities as defined in Table 23 -K of the Building Code. 4. Buildings designated as historical landmarks or preservation districts as designated by ordinance of the City Council, provided such buildings comply with all the requirements provided in said Ordinance. 5. Federal Buildings, State Buildings and Public Schools, for which the City has no jurisdiction. 6. Buildings which have been structurally upgraded in substantial accordance with the 1973, or later, edition of the Uniform Building Code. 71.05 Identification Process (a) Survey. The Building Official will cause to be completed a survey of structures in the community and research of available records to develop preliminary list of potentially hazardous buildings. As required by SB 547, the Building Official will cause said list to be submitted to the California Seismic Safety Commission. -3- 4 4 (b) Initial Owner Notification. The property owners whose buildings have been identified on the preliminary list shall be notified by the City that their building has been identified as being potentially hazardous within the scope of this Ordinance, and that if this building is on the final Listing that they will be required to have an engineering report prepared on the structural adequacy of this building. The initial notification will include a request for submission of any and all information within ninety (90) days as to the building's age, structure, occupancy, repairs or improvements to strengthen the building, and documentation if their structure may qualify for an exemption. 71.06 Final Listing of Potentially Hazardous Buildings Final Listing of Potentially Hazardous Buildings. At a scheduled public hearing, notice of which will be provided to the property owners of each building on the preliminary list, the City Council will consider all evidence, testimony and the recommendations of Building and Safety in developing a final Listing of Potentially Hazardous Buildings. 71.07 Order and Recordation Within thirty (30) days of the City Council's determination, the City Clerk shall cause to have issued an order to each and every owner of buildings on the final Listing of Potentially Hazardous Buildings. The order shall be in writing and shall be served either personally or by certified or registered mail upon the owner as shown on the last equalized assessment, and upon the person, if any, in apparent charge or control of the building. The order shall specify that the building has been determined by the City to be within the scope of this Ordinance, and, therefore is required to prepare an engineering report as outlined in Section 71.08 of this Ordinance. Said engineering report shall be submitted to the City's Building and Safety Division within six (6) months of the date of the mailed notice. At the time that the aforementioned order is served, the City Clerk shall file with the office of the County Recorder a certificate stating that the subject building is within the scope of this Ordinance and that the owner has been ordered to structurally analyze the building and file an engineering report with the City within six (6) months of that date. 71.08 Appeal from Order The owner of the building may appeal the building official's initial determination that the building is within the scope of this Chapter to the Board of Appeals established by Section 204 of the Building Code. Such appeal shall be filed with the Board within thirty (30) days from the service date of the order described in Section A2348(d)3. Any such appeal shall be decided by the Board no later than ninety (90) days after writing and the grounds thereof shall be stated clearly and concisely. Appeals or requests for modifications from any other determinations, orders or actions by the building official pursuant to the Chapter shall be made in accordance with the procedures established in Sections 105 and 106 of the Building Code. 71.09 Engineering Reports (a) Preparation of Reports. Building owners of potentially hazardous buildings shall employ a civil or structural engineer to prepare the investigation and engineering report outlined below and as referenced to Appendices A and B. -4- 475 (b) Purpose. The engineer shall investigate, in a thorough and unambiguous fashion, the buildings' structural systems that resist the forces imposed by earthquakes and to determine if any individual portion or combination of these systems is inadequate to result in a structural failure (collapse or partial collapse.) (c) General. Each building shall be treated as an individual case without prejudice or comparison to similar type or age building which may have greater or lesser earthquake resistance. Generalities or stereotypes are to be avoided in the evaluation process by focusing on the specifics of the structural system of the building in question and the local geology of the land on which the building is constructed. (d) Level of Investigation. Some buildings may require extensive testing and field investigation to uncover potential structural deficiencies, while others will allow the same level of overall evaluation by a less complicated process due to simplicity of design or the availability of original or subsequent alteration design or construction documents. (e) Format for the Report. The following is a basic outline of the format each engineering report should follow. This outline is not construed to be a constraint on the professional preparing the report, but rather to provide a skeleton framework within which individual approaches to assembling the information required by the Ordinance may be accomplished. It also will serve as a means for the City to evaluate the completeness of each report. 1. General Information. A description of the building including: (i) street address; (ii) the type of occupancy use within the building, with separate uses that generate different occupant loads indicated on a plan showing the square footage of each different use; (iii) plans and elevations showing the location, type and extent of lateral force resisting elements in the buildings (both horizontal and vertical elements); (iv) a description of the construction materials used in the structural elements and information regarding their present condition; (v) the date of original construction, if know, and the date, if known, of any subsequent additions or substantial structural alterations of the building; and (vi) the name and address of the original designer and contractor, if known, and the name and address of the designer and contractor, if known, for any subsequent additions or substantial structural alterations. 2. Investigation and Evaluation of Structural Systems. All items to be investigated and the methods of investigation for each type of building under consideration are contained in Appendices A and B, attached hereto. 476 3. Test Reports. All field and laboratory test results shall be included in the report. Evaluation of the significance of these test results shall be made with regard to each structural system or typical connection being evaluated. This evaluation may be limited to a statement of the adequacy or inadequacy of the system or connection based on the lateral load demand it would be required to resist by calculation. If tests reveal inadequacy, a conceptual solution must be included in the report. 4. Conclusions. Based on the demand /capacity ratio and the specific evaluation items contained in Appendices A and B, a statement shall be provided explaining the overall significance of the deficiencies found to exist in the building's lateral force resisting system regarding potential collapse or partial collapse failure. 5. Recommendations. An appropriate solution, which could be used to strengthen the structure to alleviate any collapse or partial collapse threat, shall be specified. (f) Exceptions and Alternatives. Exceptions to the specific items required to be included in an engineering report may be granted by the Building Official upon review of a written request from the engineer preparing the report. Such a request shall provide evidence that adequate information concerning the required item(s) can be determined by alternate means or that conclusion can be made about the item without following the solution called for in the appropriate appendix. The purpose of granting such exceptions shall be to reduce the costs or disruption that would result from taking required actions, when it can be shown that they are unnecessary to provide information available by other equivalent means. In no case will an exception be granted which would result in an item not being completely evaluated. The decision of the Building Official in granting exceptions is final. 71.09 Review of Reports (a) City Building and Safety Officials will review the report, with the assistance of civil and structural engineers as necessary, to determine whether the report conforms with the requirements of this Ordinance. (b) The cost of this review shall be recovered by a fee assessed from the building owner based on the time required for the review. This fee amount may be deducted from or partially credited to the plan checking fee collected for any future construction work that deals directly with correcting any of the structural inadequacies specified in the engineering report. (c) Copies of the engineering report shall be available to interested individuals for a standard copying fee or may be reviewed at the Building and Safety Offices during regular office hours. 71.10 Responsibilities of Building Owners (a) Availability of Report. The report shall be available to the tenants of the buildings. (b) If the building is found in compliance, another notice of that fact will be recorded to that effect. (c) Letter of Intent. A building owner shall submit a letter to City Building and Safety Office within six (6) months of the date the engineering report was submitted, indicating the owner's intentions for dealing with the potential collapse hazards found to exist in the building. -6- 71.11 Status Reports The Building Official shall submit periodic reports, not less than annually, to the City Council on the status of the seismic hazards identification program. The reports shall include information regarding the number of buildings analyzed, the severity of the structural inadequacies discovered and any action taken by individual building owners to correct these inadequacies. 71.12 Abatement of Dangerous Buildings If satisfactory progress is not made or intent plans of the building are not followed, the City may process the structure as a Dangerous Building pursuant to City Code Section 13 -13 et seq. 71.13 Remedies It shall be unlawful for the owner of a building identified as being in the scope of this Ordinance to fail to submit a report on either building collapse hazards or external hazards, provide notice or to fail to submit a letter to intent within the time periods specified in this Ordinance. The following remedies are available to the City: (a) The City may seek injunctive relief on behalf of the public to enjoin a building owner's violation of this Ordinance. (b) A building owner violating this Ordinance shall be guilty of a misdemeanor and, upon conviction thereof, shall be punishable in accordance with Section 1 -7 of the Code of the City of Cypress. SECTION II. The City Council hereby finds that this Ordinance has a statutory exemption pursuant to the California Environmental Quality Act (CEQA). SECTION III. If any section, subsection, subdivision, sentence, clause, phrase, or portion of this Ordinance, is for any reason held to be invalid or unconstitutional by the decision of any court of competent jurisdiction, such decision shall not affect the validity of the remaining portions of this Ordinance. The City Council hereby declares that it would have adopted this ordinance, and each section, subsection, subdivision, sentence, clause, phrase, or portion thereof, irrespective of the fact that any one or more sections, subsections, subdivisions, sentences, clauses, phrases or portions thereof be declared invalid or unconstitutional. SECTION IV. The City Clerk is hereby authorized and directed to certify as to the passage of this Ordinance and to give notice thereof by causing copies of this Ordinance to be posted in three public places throughout the City. FIRST READ at a regular meeting of the City Council of said City held on the 13th day of August 1990, and finally adopted and order posted at a regular meeting held on the 27th day of August , 1990. Y OF THE CITY OF C RESS -7- 477 473 ATTEST: CIT CLERK F HE C TY OF CYPRESS STATE OF CALIFORNIA ) COUNTY OF ORANGE ) SS I, DARRELL ESSEX, City Clerk of the City of Cypress, California DO HEREBY CERTIFY that the foregoing Ordinance was duly adopted at a regular meeting of the City Council of the City of Cypress, held on the 27th day of August , 1990, by the following roll call vote: AYES: 4 COUNCIL MEMBERS: Arnold, Bowman, Kerry and Kanel NOES: 0 COUNCIL MEMBERS: None ABSENT: 1 COUNCIL MEMBERS: Age CITYCLERK: OF THE' CITY OF CYPRESS 479 APPENDIX A Procedures for Investigation of All Buildings (Except Unreinforced Masonry Bearing Wall Types) (a) Preliminary Field Survey. Provide drawings of the building in plan, elevation and section sufficiently detailed to reveal the correct dimensions of the spans and extent of all structural elements in the building, including openings in walls and changes in framing directions or other data which will be used to evaluate the building. (b) Areas of Special Investigation. 1. Specify the type of roof diaphragm used in the building and its capacity for transfer of lateral forces. 2. If the building is multi -story specify the existing floor diaphragm at each level above the foundation and give its capacity for transfer of lateral forces. 3. Specify the types and spacing of connections used at each level to transfer the forces of the horizontal diaphragms into the vertical shear resisting elements of the structure, and the capacity for transfer of each type of connection present in the building. 4. Specify the type of vertical structural elements which resist lateral forces and their individual capacities as determined either by testing or use of standard values for the types of construction found in the vertical elements. 5. Specify the type and spacing of connections used to connect vertical shear resisting elements to each other and to the building foundation, and the capacity for transfer of each type of connection present. 6. Specify the type of foundation system used and note any evidence of settlement. 7. Specify the type of connection used to attach wall appendages or precast wall elements to the structural frame. Standards for the Analysis and Evaluation of All Buildings (Except Unreinforced Masonry Bearing Wall Types) (a) Purpose. The objective of these investigations is to identify and quantify the structural inadequacies that may be present in a building which could lead to a collapse or partial collapse during an earthquake. The focus of the reports should be 1) determining the potential life safety threat that the building presents to its occupants and 2) the potential threat to pedestrians or occupants of adjacent buildings from falling external hazards. (b) Capacity vs. Demand of the Existing Structural System and Its Elements. 1. Define the overall types of lateral force resisting system used in the building based on Table 23 -1 of the 1973 Uniform Building Code. If the building has a dual or hybrid system, describe the systems and explain how they function both in combination and separately to justify the "K" factor to be chosen. 2. For each type of diaphragm, shear wall, moment frame, braced' frame and interconnection of lateral force resisting systems provide an analysis of the loads (demand) which these elements would be subject to based on the design parameters set forth in the 1973 edition of the Uniform Building Code. 4S0 3. For each type of diaphragm, shear wall, frame and interconnection of lateral force resisting system determine a maximum capacity based on currently accepted or published allowable values, adjusted as appropriate for the material involved when used to resist earthquake forces. 4. Provide a ratio of capacity to demand for each system or interconnection evaluated in (2) and (3) above and provide a statement of the significance of this ratio, regarding the potential for failures which could lead to a collapse, considering the materials used and the type of lateral force resisting system present. (c) Specific Evaluation Items. The report shall contain a statement regarding the significance of each item in this section which is found to occur in the building. (1) General. A. Assess the condition of the structure, the quality of workmanship, the level of maintenance and the type of construction with regard to the potential loss of strength in the structural systems due to decay or deterioration. B. Assess the redundancy exhibited in the structural system and the reserve capacity that elements of the system may provide. C. Assess the presence or lack of ductility in the lateral force resisting elements and ductility differences due to the use of dissimilar materials in the horizontal and vertical diaphragms. D. Assess how adequately the building is tied together in an overall sense to allow the lateral force resisting systems an opportunity to receive the forces they are designed to resist. (2) Geometry. A. Consider how and where torsional (rotation) forces induced by the eccentricity of the building center of mass to its center or rigidity, are taken into the lateral force resisting system and identify the individual elements which will transmit these additional forces. Assess the potential capacity these elements have to resist the additional loads from this source. B. Consider the effect of discontinuities in the lateral force resisting systems with regard to the existence of adequate ties, boundary members, chords or drag struts, etc. to allow redistribution of forces. Assess the capacity of the systems or elements which would receive the redistributed forces if adequate ties exist. C. Consider the effects of reentrant corners (including the shape of individual columns) and assess their contribution to the response of the building at locations where they occur. (3) Building Separation. A. Consider the effects of adjoining buildings, which may have different vibration periods resulting in con - synchronized movement of the adjacent exterior walls, placing out of plane impact forces on these walls. B. Assess the level of drift control, particularly at open storefronts and the actual physical separation distance between the exterior walls of the building and adjoining building walls. 481 C. Assess condition where the all of a building on one property provides support for structural elements of the adjoining property's building. (4) Non - Ductile Reinforced Concrete Frames. A. Consider non - ductile frames which act alone without the benefit of shear walls or braced frames. B. Assess the level of compression or shear forces due to existing vertical loads on the critical supporting elements of the frame. C. Assess masonry infill walls between frame members and their effect on the forces a column /beam joint will be subjected to when attempting to transmit lateral forces into these walls. (5) Precast Concrete Connections. A. Assess the effects of temperature creep and shrinkage of concrete surrounding welded insert connections to precast systems and elements. B. Consider the potential brittle failure of such connections. (6) Non - Structural Elements. A. Assess the effect that partitions, infill walls, precast concrete exterior (architectural) elements and ceiling systems, which have considerable strength and stiffness characteristics, may have on the overall response of the building. B. Assess the effect of inadvertent bracing by non- structural elements such as infill walls, stair stringers or other situations of localized restraint on columns. C. Assess the potential stress concentrations at the unrestrained ends of columns which may result from partial restraint or bracing of columns. (7) Site Geology. A. Consider the maximum ground shaking intensity for the building site and liquefaction potential or susceptibility by using available earthquake hazard maps. B. Assess any existing site specific geology /soils reports to gauge the effects that the local conditions may have on the overall response of the building. APPENDIX B Procedures for Investigation of Unreinforced Masonry Bearing Wall Buildings (a) Preliminary Field Survey. Prepare framing plans for roof and floors noting all beams, trusses or major lintels of all URM piers or pilasters. Prepare elevations of all URM walls noting all openings in the walls and any discontinuities above the building base. (b) made: Special investigations of the following nature must be 1. Note all parts of the vertical load carrying system that may act as ties to lateral load- resisting elements, to determine the elements or systems that may control relative displacements between the building's base, floors and roof. 2. Note on floor plans all interior crosswalls that are continuous between floors or floor and roof, even if the connection of such walls to the floor or roof is only by finishes. 3. Draw the relationship of roof or floor framing and ceiling framing to determine the extent and method if any, of their inter - connection. 4. Draw the support systems for URM walls that are not continuous to the building base noting the materials used to provide that support. (i.e., steel, frame, concrete frame, etc.) 5. Draw on floor and roof plans the extent of sheathing and finish materials and describe their nature and nailing pattern. Note any difference in material used which could lead to substantial variations in diaphragm stiffness. Opening of floors or roof adjacent to URM walls must be noted. Note the type of roofing system currently in place and note if this roofing is applied directly to the main roof deck or if there are locations where it is on a cricket or other superimposed deck. (c) Investigation of current anchorage or URM walls to floors and roof. Show the location of all wall anchors on the floor /roof plans and specify their spacing, size, and method of connection. Details of the existing anchorage system should be prepared. Embedded portions of anchors must be exposed to determine this level of detail. A minimum of two percent (2 %) or two (2) anchors exposed per floor or roof level should establish average conditions. (d) Investigation of existing URM walls. Investigate the following items if they occur in the building, and determine: 1. The thickness of URM wall at all levels and location of any changes in thickness. 2. The materials used for lintels and masonry arches and their bearing area on columns or piers. 3. The materials used in columns or piers supporting lintel beams or arches. 4. The height of parapets, cornices, and gable ends of URM walls above the uppermost existing anchorages. 5. The anchorage or bonding of terra cotta, cast -stone or similar facing to the back up wythes of brickwork at cornices and other architectural appendages. 483 6. The coursing of exterior wythes of masonry, the bonding of wythes of masonry, and the materials used in each wythe. 7. The condition of mortar joints and areas of lightly unburned brick should be noted in the wall elevations. Existing cracks in wall elements should also be noted. (e) Testing. The testing of existing anchorage systems must be made to determine an average capacity. Testing shall be accomplished in accordance with the following requirements. 1. Existing Wall Anchors of URM Buildings. Ten (10) percent of existing rod anchors shall be tested in pullout by an approved testing laboratory. The minimum tested quantity shall be four (4) per floor or roof level, with two (2) tests at walls with framing perpendicular to the walls and two (2) at walls with framing parallel to the wall. The test apparatus shall be supported on the masonry wall at a minimum distance of the wall thickness from the anchor tested. Where due to obstructions this is not possible, details of the condition encountered and the alternate method used must be included in the test result report, with calibration adjustment for conditions where the reaction of the test apparatus contributes to the tension value of the anchor. The rod anchor shall be given a preload of 300 points prior to establishing a datum of recording elongation. The tension test load reported shall be recorded at 1/8" relative movement of the anchor to the adjacent masonry wall surface. The testing of existing URM walls to determine the allowable bed - joint shear is required in accordance with the following requirements. 2. In Place Shear Tests of Brick Masonry. The bed joints of the outer wythe of the masonry shall be tested in shear by laterally displacing a single brick relative to the adjacent bricks in that wythe. The opposite head joint of the brick to be tested shall be removed and cleaned prior to testing. Steel bearing plates of the full dimension of the brick shall be inserted at each end of the test jack. The bearing plates shall not contact the mortar joint. The minimum quality mortar in 80 percent of the shear tests shall not be less than the total of 30 psi when reduced to an equivalent zero axial stress. The shear stress shall be based on the gross area of both bed joints and shall be that at which movement of the adjacent brick is first observed. The minimum quantity of tests shall be two (2) per wall or line of wall elements resisting a common force (i.e., per story) or one (1.) per 1,500 square feet of total URM wall surface, with a minimum of 8 tests for any building. The tests should be conducted at least two brick courses above or below the bond course and be distributed vertically to include a variety of dead load surcharge situations. The exact test location shall be determined at the building site by the engineer responsible for the investigation and the distribution of such tests must be approved by the building official prior to actual testing. In single story buildings, the wall above the lintel beam at an open storefront need not be tested. 4S4 Standards for the Analysis and Evaluation of Unreinforced Masonry Bearing Wall Buildings. (a) Analysis. 1. General The total lateral seismic forces should be computed in accordance with the following equation: V= IKCSW The value of KCS need not exceed the value set forth in Table B1 -1. The value of I shall be equal to 1.0. The value of W shall be as set forth in the Uniform Building code. 2. Lateral Forces on Elements of Structures. Parts or portions of buildings and structures shall be analyzed for lateral loads in accordance with Chapter 23 of the UBC but not less than the value of the following equation: Fp - ICpSWp For the provisions of this section, the product of IS need not exceed 1.0. The value of Cp and Wp shall be as set forth in the UBC. Exception: Unreinforced masonry walls may be analyzed in accordance with Section (b). 3. The elements of buildings required to be analyzed shall include the following: Wall height to thickness ratio. Tension bolts for bending. In -plane shear forces. Parapets. Diaphragm stress and diaphragm chords at floors and roof. 4. Anchorage and Interconnection. Anchorage and interconnection of all parts, portions and elements of the structure shall be analyzed for lateral forces in accordance with the # #'UBC and the formula in Subsection 2 above. Masonry walls shall be anchored to all floors or roof to resist a minimum of 200 pounds per linear foot of load per analyses acting normal to the wall at the level of the floor or roof or will be considered inadequate. 5. Required Analysis. Except as modified herein, the analysis and recommended structural alteration of the structure shall be in accordance with the analysis specified in the currently adopted edition of the Uniform Building Code. A complete, continuous load path from every part or portion of the structure to the ground shall be shown to exist for required lateral forces. All parts, portions or elements of the structure shall be shown to be interconnected by positive means. 6. Analysis Procedure. Stresses in materials and existing construction utilized to transfer seismic forces from the ground to parts of portions of the structure shall conform to those permitted by the UBC and those types of materials of construction specified under the Materials of Construction Section (b). In addition to the seismic forces required, unreinforced masonry walls shall be analyzed as specified in the UBC to withstand all vertical loads. 4.5 When calculating shear or diagonal tension stresses due to seismic forces, existing masonry shear walls may be allowed to resist 1.0 times the required forces in lieu of the 1.5 factor required in unreinforced masonry walls. Walls not capable of resisting the required design forces specified in this appendix shall be deemed inadequate. Exception: Unreinforced masonry walls which carry no design loads other then their own weight may be considered as veneer if they are adequately anchored to elements which are not part of the existing lateral force resisting system. 7. Existing Materials. When stress in existing lateral force resisting elements are due to a combination of dead loads plus live loads plus seismic loads, the allowable working stress specified in the UBC may be increased 100 percent. However, no increase will be permitted in the stresses allowed in Section (b). The stresses in members due only to seismic and deal loads shall not exceed the values permitted in the UBC. 8. Allowable Reduction of Bending Stress by Vertical Load. Calculated tensile fiber stress may be reduced by the full direct stress due to vertical deal loads. (b) Materials of Construction. 1. General All materials permitted by this code, including their appropriate allowable stresses and those existing configurations of material specified herein, may be utilized to show adequacy of existing construction. 2. Existing Materials. Unreinforced masonry walls analyzed in accordance with this appendix may provide vertical support for roof and floor construction and resistance to lateral loads. The bonding of such walls shall be as specified in the UBC. Tension stresses due to seismic forces acting normal to the wall may be neglected if the wall does not exceed the Height to Thickness ratio and the in -plane shear stresses due to seismic loads set forth in Table B1 -2. If the Wall Height or Length to Thickness ratio exceeds the specified limits, the wall will be considered inadequate unless braced by vertical members designed to satisfy the requirement of the UBC. The deflection of such bracing members at design loads shall not exceed one -tenth of the wall thickness. Exception: The wall may be supported by flexible vertical bracing members designed in accordance with the appendix if the deflection at design spacing of vertical bracing members shall not exceed one -half the unsupported height of the wall or ten feet, whichever is less. 3. Existing Roof, Floors, Walls, Footings and Wood Framing. Existing materials, including wood shear walls may be used as part of the lateral load resisting system, provided that the stresses in these materials do not exceed the values shown in Table B1 -3. Wood shear walls may be recommended to strengthen portions of the existing seismic resisting system. 4. Minimum Acceptable Quality of Existing Unreinforced Masonry Walls. All unreinforced masonry walls, utilized to carry vertical loads and seismic forces parallel and perpendicular to the wall plane shall be tested as specified in Section (e) of the investigation portion of this appendix. All masonry shall be of a quality not less than the minimum standards established or shall be considered inadequate. Pointing of mortar of all masonry wall joints may be performed prior to testing if joints are raked and cleaned to remove loose and deteriorated mortar. Mortar shall be Type S or N. except masonry cements shall not be used. All preparation and pointing shall be done under the continuous inspection of a special inspector, whose reports shall be included in the final report. 5. Determination of Allowable Stresses for Design Methods Based on Test Results. Design seismic in -plan shear stresses shall be related to test results in accordance with Table B1 -4. Intermediate values between 3 and 10 psi may be interpolated. Compression stresses for unreinforced masonry having a minimum design shear value of 3 psi shall not exceed 100 psi. Design tension values for unreinforced masonry shall not be permitted. 6. Construction Details. All unreinforced masonry walls shall be anchored at all floors and roof with tension bolts through the wall or by existing rod anchors at a maximum spacing of six feet. All existing rod anchors shall be secured to the joists to develop the required forces. Testing of the existing rod anchors shall be conducted according to Section (e) of the investigation portion of this appendix. Diaphragm cord stresses of horizontal diaphragms shall be developed in existing materials or be considered inadequate. Where trusses or beams other than rafters and joists are supported on masonry piers, these piers must be shown to provide adequate support during seismic loading. Parapets and exterior wall appendages not capable of resisting the forces specified in this appendix shall be considered hazardous, and the methods for property anchorage must be developed.