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HomeMy WebLinkAboutAGENDA REPORT 1990 0418 CC REG ITEM 12AITEM Lz -A- ORDINANCE N� AN ORDINANCE OF THE CITY OF MOORPARK, CALIFORNIA, AMEND- ING TITLE 8 OF THE MOORPARK MUNICIPAL CODE BY ADDING CHAPTER 8.08, RELATING TO EAI'THQUAKE HAZARD REDUCTION IN CERTAIN EXISTING BUILDINGS. WHEREAS, a noticed public hearing has been held by the City Council, at which time all interested persons had the opportunity to appear and be heard on the mat ~ :er of earthquake hazard reduc- tion in certain existing buildinq;, NOW, THEREFORE, THE CITY COUNCIL OF THE CITY OF MOORPARK, CALIFORNIA, DOES ORDAIN AS FOLLOW:': Section 1. That Title 8 of the Moorpark Municipal Code is amended by adding Chapter 8.08 t:c; read as follows: CHAPTER 8. 8 EARTHQUAKE HAZARD REI:)UCTION IN EXISTING BUILDINGS NOTE: Code reference - 1988 Uniform Building Code. SEC. 8.08.100 PURPOSE The purpose of this chapter is to promote public safety and wel- fare by reducing the risk of death or injury that may result from the effects of earthquakes on unreLnforced masonry bearing wall buildings. Such buildings have been widely recognized for sus- taining life- hazardous damage, including partial or complete col- lapse during moderate to strong earthquakes. The provisions of this Chapter are not intended to cause com- pliance with the requirements for the Planned Development Permit as specified by Division 8, Chapter 1: Zoning so long as the provisions of Article 42, Non-Conforming Buildings and Non - Conforming Uses are adhered to. The provisions of this chapter are intended as minimum standards for structural seismic resistance established primarily to reduce the risk of life loss or injury. Compliance with these standards will not necessarily prevent loss :)f life or injury or prevent earthquake damage to rehabilitated buildings. This chapter does not require alteration of existing electrical, plumbing, mechani- cal or fire safety systems unless they 7onstitute a hazard to life or property. This chapter provides systematic procedures and standards for identification and classification of unreinforced masonry bearing wall buildings based on their present use. Priorities, time periods and standards are also established under which these buidings are required to be structurally analyzed and anchored. Where the analysis finds deficiencies, this chapter requires the building to be strengthened or demo`iished. Qualified Historical Buildings stall be strengthened, where necessary, in accordance with the state Historical Building Code (SHBC) established under Part 8, T tle 24 of the California Ad- ministrative Code,. SEC. 8.08.110 SCOPE The provisions of this chapter shall apply to all buildings which on the effective date of this ordinance have unreinforced masonry bearing walls as defined •erein. EXCEPTION: This division shall not apply to detached one or two family dwellings and detached apartment houses containing less than 5 dwell :gig units and used solely for residential purposes. The requirement for a Planned Development Permit as specified by Division 8, Chapter 1: Zoning shall not be imposed upon any property which adheres to this chapter so long as the provisions of Article 42, Non - Conforming Bu ldings and Non - Conforming Uses are adhered to. SEC. 8.08.120 DEFINITIONS For purposes of this chapter, the applicable definitions in Sec- tion 2302 and 2312 of the Uniform Building Code (1) shall apply: ESSENTIAL BUILDING: Any building housing a hospital or other medical facility having surgery or emergency treatment areas; fire or police stations; munici.pa: government disaster operation and communication centers. HIGH RISK BUILDING: Any bui.ding, trot classified an essen- tial building, having an occupant load c�f 100 or more, as deter- mined by Section 3302 (a). EXCEPTION: A high risk build,.ng .shall not include the following: 1. Any building having exterior walls braced with masonry crosswalls or wood frame crosswalls spaced less than 40 feet apart in each story. Crosswalls shall be full story height with a minimum length of 1 1/2 times the story height. 2. Any building used for its intended purpose, as determined by the building cf ic:_al, for less than 20 hours per week. LOW RISK BUILDING: Any builriing,, not classified as an es- sential building, having an occupant load of less than 20 oc- cupants as determined by Sectior.� 3'02 (a) MEDIUM RISK BUILDING: Any bui6_ding, not classified as a high risk building or an essential buiAing, having an occupant load of 20 occupants or more as determined by Section 3302(a). 2 UNREINFORCED MASONRY BEARING WALL: A masonry wall having all of the following characteristics: 1. Provides the vertical support for a floor or roof. 2. The total superimposed :load is over 100 pounds per linear foot. 3. The area of reinforcing steel is less than 50 percent of that required by Section :'407(h) SEC. 8.08.130 RATING CLASSIFICAT'I ")NS The rating classifications shown in Table No. 8.08 -A are hereby established and each buiding within the scope of this chapter shall be placed in one such ratan( classification by the building official. The total occupant goad of the entire buiding as determined by Section 3302(a) s.j:all be used to determine the rating classification. EXCEPTION: For the purpose c: >f this chapter, portions of buildings constructed to act independently when resisting seismic forces may be placed _n separate rating classifications. SEC. 8.08.140 GENERAL REQUIREMENTS The owner of each building within the scope of this chapter shall cause a structural analysis of the building to be made by a civil or structural engineer or architect licensed by the State of California. If the building does not meet the minimum earthquake standards specified in this chapter, the owner shall either cause it to be structurally altered tc conform to such standards; or cause the building to be demolished. The owner of a building within the scope of this chapter shall comply with the requirements set forth above by submitting to the building official for review withi:i the stated time limits: (a) Within 270 days after the service of the order, a struc- tural analysis, which is subject ::o approval by the building of- ficial, and which shall demonstrate that the building meets the minimum requirements of this Chapter; or (b) Within 270 days after °:.he service of the order, the structural analysis and plans for the proposed structural altera- tions of the buiding necessary t.., comply with the minimum re- quirements of this chapter; or (c) Within 120 days after service of the order, plans for the installation of wall anchors ...n accordance with the require- ments specified in Section 8.08.1,60(c); or (d) Within 270 days after t`:e service of the order, plans for the demolition of the buildin, After plans are submitted and approved by the building official, the owner shall obtain a building permit, commence and complete the required construction or demolition within the time limits set forth in Table No.8.08 -B. These time limits shall begin to run from the date of order is served it accordance with Section 8.08.150(a) and (b).. Owners electing to comply with Subsection (c) of this section are also required to comply with Subsection (b) or (d) of this sec- tion provided, however, that the 270 -day period provided for in such Subsections (b) and (d) and the time limits for obtaining a building permit, commencing construction and completing construc- tion for complete structural alterations or buiding demolition set forth in Table No. 8.08 -B shall be extended in accordance with Table No. 8.08 -C. Each such extended time limit, except the time limit for commencing construction shall begin to run from the date the order is served in a,:,cordance with section 8.08.150. The time limit for commencing construction shall commence from the date the building permit is, i-,sued. SEC. 8.08.150 ADMINISTRATION (a) Service of Order. The building official shall issue an or- der, to the owner of each building within the scope of this chapter in accordance with the minimum time periods for service of such orders set forth in Table N. 8,08 -C. The minimum time period for the service of such orders shall be measured from the effective date of Chapter 8.08. Upon receipt of a written re- quest from the owner, the building official shall order a build- ing to comply prior to the norma; service date for such building set forth in this section.. (b) Contents of Order. 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 spec:.fy that the building has been determined by the building official to be within the scope of this chapter and, therefore, is required to meet the minimum seismic standards of this chapte7. The order shall specify the rating classification of the building and shall be accompanied by a copy of Section 8.08.150 which sets forth the owner's alterna- tives and time limits for compl:ia; ^e. (c) Appeal Form Order. The owner or person in charge or control of the building may appeal to the City Council the building official's initial determination 1,;hat the building is within the scope of this chapter. Such appeal shall be filed with the building official within 60 days from the service date of the order described in Section 8.08.1')(b) Any such appeal shall be 4 decided by the Council no later t::an 60 days after the date that the appeal is filed. Such appeal shall be made in writing the grounds thereof shall be stated c:1-ar_'.y and concisely. Appeals or requests for slight modific=ations from any other determinations, orders or actions by the building official pur- suant to this chapter, shall be made in accordance with the nor- mal appeal procedures established n `his code. (d) Recordation. At the time that the aforementioned order is served, the building official shall .file with the office of the county recorder a certificate stating that the subject building is within the scope of Chapter � 08 - Earthquake Hazard Reduc- tion in Existing Buildings. The certificate shall also state that the owner thereof has been ,r.dered to structurally analyze the building and to structurally alter_ or demolish it where it is not found to comply with Chapter t. 03 If the building is found not tc be within the scope of this chap- ter, or as a result of structura alterations or an analysis is found to be structurally capable of resisting minimum seismic forces required by this chapter; or is demolished; the building official shall file with the office of the county recorder a cer- tificate terminating the status os the subject building as being classified within the scope of C1.apter X3.08 - Earthquake Hazard Reduction in Existing Buildings. (e) Enforcement. If the owner or other person in charge or con- trol of the subject building fa.ls to comply with any order issued by the building official pursuant to this chapter within any of the time limits set forth Ln section 8.08.140, the build- ing official shall order the entire building vacated and remain vacated until such order has been complied with. If compliance with such order has not been accomplished within 90 days after the date the building has been ordered vacated, or by such addi- tional time as may have been granted by the City Council, the building official may order demoll.tion of the building in accor- dance with the Abatement of �an:;erous Buildings provisions of this code. 5 Sec. 8.08.160 ANALYSIS AND DESI! ;N (a) General. Every structure within the scope of this Chapter shall be analyzed and constructed to resist minimum total lateral seismic forces assumed to act nonroncurrently in the direction of each of the main axes of the st °'ucture in accordance with the following equation: V =ZICW (8.08 -1) The value of IC /R, need not exceed the values set forth in Table No. 8.08 -D based on the applicable rating classification of the building. (b) Lateral Forces on Elements of Structures. Parts or portions of structures shall be analyzed and designed for lateral loads in accordance with subsection 8.08.:60(a) and section 2312 of the Uniform Building Code but not leis than the value from the fol- lowing equation: Fp -ZICp WF, 1 8. 08-2) For the provisions of this subse,.,ti.on, the values of I are the values as set forth in Table No. 3.08 -E EXCEPTION: Unreinforced masonry walls in buildings not having a rating classification of I may be analyzed in accordance with Section 8 08 170 The value of Cp need not exceed the values set forth in Table 8.08 -F. (c) Anchorage and Interconnection. Anchorage and interconnec- tion of all parts, portions and elements of the structure shall be analyzed and designed for lateral forces in accordance with Table No. 8.08 -F of this code and the equation FI,= ZICF,Wp as modified by Table No. 8.08 -E. Minimum anchorage of masonry walls to each floor or roof shall resist a minimum force of 200 pounds per linear foot acting normal tc the wall at the level of the floor or roof. (d) Level of Required Repair. Alterations and repairs required to meet the provisions of this chapter shall comply with all other applicable requirements of the Uniform Building Code unless otherwise specifically provided f r in this chapter. (e) Required Analysis. 1. General. Except as modified herin, the analysis and design relating to the structural alteration of existing structures within the scope of this chapter shall be in accordance with the analysis srocifi.ed in Chapter 23 of the Uniform Building Code. In addition, t-he compatibility of the roof diaphragm stiffness with the out-:)f -plane stability of the unreinforced masonry bearing walls of the story immediately below the roof system shall be verified in a- cordance with the provi- sions of Section 8.08.190. Exception: Buildings with rigid c.)ncrete or steel and con- crete roof diaphragms shall use the ' /t values for "all other buildings" in Table No. 8.08 -G 2. Continuous Stress Path. A complete, continuous stress path from every part or portion of the structure to the ground shall be provided for the required hor�_zontal forces. 3. Positive Connections. All parts, portions or elements of the structure shall be interconnected by positive (f) Analysis Procedure. 1. General, Stresses in materials and existing construction utilized to transfer seismic forces from the ground to parts or portions of the structure shall not exceed the stresses permitted by the Uniform Building Code except that existing materials and stresses may xe as specified in section 8.08.170. 2. Connections. Materials and connectors used for inter- connection of parts and portions of the structure shall conform to the Uniform Building Code. Nails may,. be used as part of an approved connector. 3. Unreinforced Masonry Walls. Except as modified herein, unreinforced masonry walls shall be analyzed as specified in the applicable parts of Sections 2406, 2407 and 2409 to withstand all vertical loads as specified in Chapter 23 of the Uniform Building Code in addition to the seismic forces required by this chapter. Substantial changes in wall thickness or stiffness shall be con- sidered in the analysis for out -of -plane and in -plane wall stability, and the wall shall be restrained against out -of -plane instability by anchorage and bracing to the roof or floor diaphragm in accordance with Section �0E.160(c). Exception: Variations in wall stiffness caused by nominal openings such as windows and exit doo -s need not be considered. The 50 percent increase in the seismic force factor for shear walls as specified in Section 2407(h!4F(i) of the Uniform Build- ing Code may be omitted in the comp:tation of seismic loads to existing shear walls. 7 No allowable tension stress wili be permitted in unreinforced masonry walls. Walls not capable of resisting the required design forces specified in this chapter shall be strenqthened or shall be removed and replaced. EXCEPTION: 1. Unreinforced masonry walls in buildings not classified as a Rating Classification I pursuant to Table No. 8.08 -A may be analyzed ,..r accordance with Section 8.08.170. 2. An unreinforced masonry wall which carries no design loads other than its own weight may be considered as veneer if it is adequately archored to new supporting elements., (g) Combination of Vertical and Seismic Forces. 1. New Materials. All new materials introduced into the structure to meet the requirements of this section which are subjected to com- bined vertical and horizontal forces shall comply with Section 2303(f). 2. Existing Materials. when stresses in existing lateral force resisting elements are due to a combination of dead loads and live loads plus seismic loads, the allowable working stress specified in the Uniform Building Code may be increased 100 per- cent. However, no increase will be permitted in the stresses al- lowed in Section 8.08.170, and the stresses in members due only to seismic and dead loads shall not exceed the values permitted by Section 2303(d) of the Uniform Building Code. 3. Allowable Reduction of Bending Stress by Vertical Load. In calculating tensile fiber stress due to seismic forces re- quired by this chapter, the maximum tensile fiber stress may be reduced by the full direct stress due to vertical dead loads. SEC. 8.08.170. MATERIALS OF CONS7'RUCTION (a) General. All materials permitted by the Uniform Building Code including their appropriate allowable stresses and those ex- isting configuration of materials specified herin may be utilized to meet the requirements of this "gapt.er (b) Existing Materials. 1. Unreinforced Masonry Walls. Unrein- forced masonry walls analyzed in accordance with this Section may provide vertical support for r•( -)f and floor construction and resistance to lateral loads. All units of both bearing and nc,:)n- bearing walls shall be laid with full shoved mortar joints; ail head, bed, and wall (collar) joints shall be solidly filled with mortar; and the bonding of adjacent wythes of multiwythe wal s steal: be as follows: i The facing and backing of such walls shall be bonded so that not less than 4 percent of the exposed face area is composed of solid headers extending not less than 4 inches into the backing. The distance between adjacent full-length. headers shall not exceed 24 inches vertically or horizontally. In walls in which a single header does not extend through the wall, headers from the op- posite sides shall overlap at least four inches, or headers from opposite sides shall be covered wit:n another header course over- lapping the header below at least four inches. Wythes of walls not bonded as described above shall be con- sidered as veneer. The veneer wythe shall not be included in the effective thickness used in calculating the height to thickness ratio and the shear capacity of the wall.. Tension stresses due to seismic for es normal to the wall may be neglected if the walls do not exceed the height to thickness ra- tion in Table No. 8.08 -G and the I-1-plane shear stresses due to seismic loads as set forth in Table No 8.08 -J. If the wall height- thickness ration exceeds the specified limits, the wall may be supported by vertical bracing members designed in accordance with Section 8.08.160. "he deflection of such bracing member at design loads shall not �xce.ed one -tenth of the wall thickness. EXCEPTION: The wall may be supported by flexible vertical bracing members designed in accordance with Section 8.08.160(b) if the deflection at design loads is not less than one quarter nor more that one -third of the wall thickness. All vertical bracing members shall be attached to floor and roof constructin for their design loads independently of required wall anchors. Horizontal spacing of vertical bracing members shall not exceed one -half the unsupported height of the wall nor ten feet. The wall height may be measured )ertically to bracing elements other than a floor or roof. Spacing of the bracing elements and wall anchors shall not exceed six feet. Bracing elements shall be detailed to minimize the horizontal displacement of the wall by components of vertical displaceents of the floor or roof. 9 2. Veneer. Veneer shall be anchored with approved anchor ties conforming to the required dewign capacity specified in Sec- tion 3004(c) and placed at a max--mum spacing of 24 inches. Exception: The Building offi.cial may accept existing veneer anchor ties provided the r.ies are in good condition and conform to the minimum size, maximum spacing and material requirements specified in w:.he provisions of the Building Code in effect at the time of construction. The existance and condition of existing veneer ties shall be verified by: 1. an approved testing laboratory which shall submit a report to the builc`ling department as a part of the structural analysis, and 2. exposing ar ::;elected representative area of not less than four ties 'or inspection by the building department. 3. Existing Roof, Floors, walls, Footings, and Wood Fram- ing. Existing materials including wood shear walls utilized in 8the described configuration may be used as part of the lateral load resisting system, prov:ide�z that the stresses in these materials do not exceed the values shown in Table No.8.08 -H. (c) Strengthening of Existing Materials. New materials including wood shear walls may be utilized ro stregthen portions of the ex- isting seismic resisting system _n the described configurations provided that the stresses do :>t exceed the values shown in Table 8.08 -I. (d) Alternate Materials. Alternate materials, designs and methods of construction may be approved by the building official in accordance with the provisions of the Uniform Building Code. (e) Minimum Acceptable Quality ,f Existing Unreinforced Masonry Walls. 1. General Provisions., 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 this subsection. All masonry quality shall equal or exceed the minimum standards established herein or shall be removed and re- placed by new materials. Alternate methods of testing may be ap- proved by the building official. The quality of mortar in all masonry walls shall be determinHd by performing in -place shear tests or by testing eight inch di +.meter •ores. The vertical wall joint between wythes (collar joint) shall be inspected at the test location : :ifter the in -place shear tests, and an estimate of the percentage of wythe to wythe mortar coverage shall be reported along with the results of the in -place shear tests. Where the exteric face is veneer, the type of veneer, its thickness and its bolding and /or ties to the struc- tural wall masonry shall also he eper,tec'. Alternative methods of testing may be approved by the building official. Nothing shall prevent pointing with mortar of all the masonry wall joints before the !_.ests are first made. Prior to any pointing, the mortar joints must be raked and cleaned to remove loose and deteriorated mortar. Mortar for pointing shall be Type S or N except that masonry cements shall not be used. All preparation and mortar pointing shall be done under the con - tinous inspection of an approved special inspector. At the con- clusion of the inspection, the inspector shall submit a written report to the licensed engineer ,)r architect responsible for the seismic analysis of the building setting forth the result of the work inspected. Such report shall be submitted to 'the building official for approval as part of the structural analysis. All testing shall be performed in accordance with the requirements specified in this subsection by 3 testing agency approved by the building official. An accurate record shall be kept of all such tests and of their locations in the building, and these results shall be submitted to the building official for approval as part of the structural analysis. 2. Number and Location of Tests. The minimum number of tests shall be as follows: a. At each of both the first and top stories, not less than two per wall line or line of wall elements providing a com- mon line of resistance to lateral forces. b. At each of all other stories, not less than one per wall elements providing a common line )f resistance to lateral forces. C. In any case, not less ,.han one per 1500 square feet of wall surface and a total of eight d. The shear tests shall be taken at locations representa- tive of the mortar conditions f.hroughout the entire building, taking into account variations in workmanship at different build- ing height levels, variations in weathering of the exterior sur- faces, and variations in the condition of the interior surfaces due to deterioration caused by .eaks and condensation of water and /or by the deleterious effects of other substances contained within the building. where thH higher h/t ratios allowed in footnotes 4 and 5 of Table 8.08 -G are to be utilized, the in- place shear tests taken at the top story shall be included in the 80 percent of the shear tests us -d to determine the minimum mor- tar shear strength. 3. In -Place Shear Tests. 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. Tae minimum quality mortar in 80 Percent of the shear tests shall ,o: be less than the total of 30 psi plus the axial stress in the wall at the area of both bed joints and shall be that at which novement of the brick is first observed. Walls with mortar values whir :h are consistently low and do not meet the minimum quality values-- speca.fied in this subsection shall be entirely pointed. 4. Core Tests. A minimum number of mortar test specimens equal to the number of required ccres shall be prepared from the cores and tested as specified herein. The mortar joint of the outer wythe of the masonry core shall be tested in shear by plac- ing the circular core section in a compression testing machine with the mortar bed joint rotated ..5 degrees from the axis of the applied load. The mortar joint tested in shear shall have an average ultimate stress of 20 psi based on the gross area. The average shall be obtained from tkie total number of cores made. If test specimens cannot be made from cores taken, then the shear value shall be reported as zero. (f) Testing of Shear Bolts. one -forth of all new shear bolts and dowels embedded in unreinforced masonry walls shall be tested by a Special Inspector using 3 t­,rque +::alibrated wrench to the following minimum torques: 1/2" diameter bolts or dowels 40 foot -lbs. 5/8" diameter bolts or dowels = 50 foot -lbs. 3/4" diameter bolts cr dowels _ 60 foot -lbs. No bolts exceeding 3/4" shall be used. All nuts shall be in- stalled over malleable iron or plate washers when bearing on wood and heavy cut washers when bearinc: on steel. (g) Determination of Allowable Stresses for Design Methods Based on Test Results. 1. Design Shear Values. Design seismic in- plane shear stresses shall be substantiated by tests performed as specified in Section 8.08.170(e) and 4 Design stresses shall be related -.o test results obtained in ac- cordance with Table No. 8.08 -.1. Intermediate values between 3 and 10 psi may be interpolated 2. Design Compression and Tension Values. 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 ne, be permitted. (h) Five percent of the existing rod anchors utilized as all or part of the required wall anchors shall be tested in pullout by an approved testing laboratory. The minimum number tested shall be four per floor, with two tests at walls with joists framing into the wall and two tests at w l 1 s with joists parallel to the wall. The test apparatus shall to supported on the masonry wall at a minimum distance of the wall thickness from the anchor tested. The rod anchor shall be given a preload of 300 lbs. prior to establishing a datum for recording elongation. The ten- sion test load reported shall. tae recorded at one - eighth inch relative movement of the anchor, and the adjacent masonry surface. Results of all tests shall be reported. The report shall include the test results as related to the wall thickness and joist orientation. The allowable resistance value of the existing anchors shall be 40 percent of the average of those tested anchors having the same wall thickness and joist orientation. (i) Qualification tests for devices used for wall anchorage shall be tested with the entire tension load carried on the en- larged head at the exterior face of the wall. Bond on the part of the device between the enlarged head and the interior wall face shall be eliminated for the qualification tests. The resis- tance value assigned the devicF shall be 20 percent of the average of the ultimate loads. SEC. 8.08.180. INFORMATION REQUIRFD ON PLANS (A) General. In addition to the seismic analysis required else- where in this Chapter, the licensed engineer or architect respon- sible for the seismic analysis cf the building shall determine and record the information requited by this Section on the ap- proved plans. (b) Construction Details. The following requirements with ap- propriate construction details shall be made part of the approved plans.: 1. All unreinforced masonry walls shall be anchored at the roof level by tension bolts through the wall as specified in Table 8.08 -I, or by approved equi,alent at a maximum anchor spac- ing of six feet. All unreinforced masonry walls shall be anchored at all floors with tension bolts through the wall or by existing rod anchors at the maximum anchor spacing of six feet. All existing rod anchors shall be secured to the joists to develop the required forces. The building official may require testing to verify the adequacy of the embedded ends of existing rod anchors. Tests when re- quired shall conform to Section 8 ')8.1.70,rh) Exception: walls need not oe anchored to ceiling systems that, because of their low mass and /or relative location with respect to the floor or foof systems, would not impose significant normal forces on ':he wall and cause our -of -plane wall failures. 13 At the roof and all floor levels, the anchors nearest the build- ing corners shall be combination shear and tension anchors lo- cated not more than two feet hori:,)ntally from the inside corners of the walls. When access to the exterior face the masonry wall is prevented by proximity of an existing build:Lng, wall anchors conforming to Items 5 and 6 in Table 8.08 -I may tie used.. Alternative devices to be used in lieu of tension bolts for masonry wall anchorage shall be ested as specified in Section 8.08.170(i). 2. Diaphragm chord stresses of horizontal diaphragms shall be developed in existing materials or by addition of new materials. 3. Where trusses and beams ther than rafters or joists are supported on masonry, independent secondary columns shall be in- stalled to support vertical loads 3f the roof or floor members. 4. Parapets and exterior wall appendages not capable of resisting the forces specified it this chapter shall be removed, stabilized or braced to insure teat the parapets and appendages remain in their original positron The maximum height of an unbrace, unreinforced masonry parapet above the lower of either the level of tension anchors or roof sheathing, shall not exceed one and one -half times the thickness of the parapet wall. If the required parapet height exceeds this maximum height, a bracing system designed for the force factors specified in Table No. 8.08 -E and Table No. 23 -J for walls shall support the top of the parapet. Parapet corrective work must be performed in conjunction with t_.l­ installation of tension roof anchors. The minimum height of a parapet. aaovE' the wall anchor shall be 12 inches. Excepton: If a reinforced oncrete beam is provided at the top of the wall, the minimum height above wall anchors may be 6 inches. 5. All deteriorated mortar joints in unreinforced masonry walls shall be pointed with Type S or N mortar (Masonry cements shall not be used). Prior to any pointing, the wall surface must be raked and cleaned to remove loose and deteriorated mortar. All preparation and pointing sha:1 be done under the continuous inspection of a special inspector certified to inspect masonry or concrete. At the conclusion of the project, the inspector shall submit a written report to the r)uildinq official setting forth the portion of work inspected.. L. 6. Repair details shall be prepared for any cracked or damaged unreinforced masonry wa l required to resist forces specified in this chapter. (c) Existing Construction. The t'ollowing existing construction information shall be made part of ":he approved plans: 1. The type and dimensions f existing walls and the size and spacing of floor and roof memr:ers. 2. The extent and type of ex,.sttng wall anchorage to floors and roof. 3. The extent and type ot parapet corrections, if any, which were performed in accordari.ce with the Uniform Building Code. 4. Accurately dimensioned floor plans and masonry wall elevations showing dimensioned openings, piers, wall thickness, heights, and veneer and anchorage . 5. The location of cracks �r damaged portions of unrein- forced masonry walls requiring rel %airs 6. The type of interior wall surfaces and ceilings, and whether reinstalling or anchor:inc of existing plaster is neces- sary. 7. The general condition of the mortar joints and whether the joints need pointing. 8. The location of the shear tests shall be shown on the floor plans and building wall elevations, and the complete test report shall be reproduced on the approved plans. 1 SEC. 8.08.190 DESIGN CHECK -- COMPATIBILITY OF ROOF DIAPHRAGM STIFFNESS TO UNREINFORCED MASONRY WALL OUT -OF -PLANE STABILITY. (a) General. The requirements >f this section are in addition to the requirements of Sections 8 08.160 and 8.08.170. The rela- tive stiffness and strength of a diaphragm governs the amount of amplification of the seismic ground motion be the diaphragm, and therefore, a diaphragm stiffness and strength related check of the our -of -plane stability of unreinforced masonry walls anchored to wood diaphragms shall be made This section contains a pro- cedure for the evaluation of the out -of -plane stability of un- reinforced masonry walls anchored to wood diaphragms that are coupled to shear resisting elemen s (b) Definitions. The followinc.: defin.-Ltions are applicable to this section: Cross wall. A wood - framed wall having a height -to- length ratio complying with Sectlo 4714(d) or Table No. 25 -I and sheathed with any of the materials described in Table No. 8.08 -K or Table No. 8.08 -L. The total strength of all cross walls located within any 40 feet length of diaphragm measured in the direction of the diaphragm span shall be not less than 30 percent of the - trength of the diaphragm in the direction of consideration.. Demand - Capacity Ratio (DCR). A ratl.o of the following: 1. Demand = lateral forces due to 33 percent of the weight of the diaphragm and the tributary weight of the walls and other element; anchored to the diaphragm. 2. Capacity = diaphragm total shear strength in the direction under consideraton as determined using the values in Table No. F „Ox. -F or Table No. 8.08 -L. 16 (c) Notations. D = depth of diaphragm, an eet, measured perpendicular to the diaphragm span. h /t= height -to- thickness rat.,o of an unreinforced masonry wall. The height shall be measured between wall anchorage levels and the thickness shall be measured through the wall cross section L = span of diaphragm between masonry shear walls or steel frames Vim= total shear capacity of cross walls in the direction of analysis immediately be --Low the diaphragm level being investigated as determined by using Tables no. 8.08 -K and 8.08 -L. v„= maximum shear strength ,.n pounds per foot for a diaphragm sheathed with any of the materials given in Tables No. 8.08 -K and 8 a8 -L Wd= Tatal dead load of the c: #iaphragm plus the tributary weight of the walls anchored to the diaphragm, the tributary ceiling and partitions and the weight of any other permanent buildino elements at the diaphragm level under investigate n. (d) Design check Procedure. I General. The demand - capacity ratio (DCR) for the building under investigation shall be calcu- lated using the following equatioi.3: DCR = 0.33Wd /2v,,D (8.08 -3) or DCR = 0.33Wd /2v.D + V_) (8.08 -4) 2. Diaphragm Deflection. The calculated DCR shall be to the left of the curve in Figure No. 8.08 -A. Where the calculated DCR is outside (to the right of) the curve, the diaphragm deflec- tion limits are exceeded, and crc,ss walls may be used to reduce the deflection. 3. Unreinforced Masonry Wa1 out -of -Plane Stability. The DCR shall be calculated discounting any cross walls. If the DCR corresponding to the diaphragm span is to the right of the curve in Figure No. 8.08 -A, the region within the curve at and below the intersection of the diaphragm span with the curve may be used to determine the allowable h/t va.lpies peir' Table No. 8.08 -G. 17 TABLE NO 8.08 -A RATING CLASSIFICATTONS TYPE OF BUILDING CLASSIFICATION Essential Building I High Risk Building II Medium Risk Building III Low Risk Building IV 18 TABLE NO 8.08 -B TIME LIMITS FOR 7OMPLIANCE (1) REQUIRED ACTION OBTAIN BUILDIP,IG BY OWNER PERMIT WITHIN Complete structural -- Alterations or 1 year Building Demolition Wall Anchor 180 days Installation COMMENCE COMPLETE CONSTRUCTION CONSTRUCTION WITHIN WITHIN 18(' days (2) 3 years 270 days 1 year (1) Where two or more buildings tinder separate ownership are to be rehabilitated simultaneously, an extension can be based on the average time requirements for the buildings involved, with a sug- gested minimum extension of 6 months. An extension could be granted on submission of a bindinc agreement the owners involved, with the actual date of complia:nc" to be determined by the build- ing official. (2) Measured from date of building permit issuance. All the other time limits are measured from the date of the order. 19 TABLE NO 8,08 -C SERVICE PRIORITIES ANI) EXTENDED TIME PROVISIONS 100 or more years 1 year III 51 to and yearn 2 years including 99 20 to and including 50 years 3 years IV Less than 20 years 4 years (Lowest Priority) TABLE NO 8.08 -D HORIZONTAL FORCE FACTORS BASED ON RATING CLASSIFICATION RATING CLASSIFICATION ZIC /R, I 0.183 II 0.138 III & IV 0.110 2C Extension of Time Minimum Time Rating Occupant if wall Anchors Periods for Classification load aiz Installed Service of Order I Any 1 7eai 0 (highest Priority) II 100 or more years 90 days 100 or more years 1 year III 51 to and yearn 2 years including 99 20 to and including 50 years 3 years IV Less than 20 years 4 years (Lowest Priority) TABLE NO 8.08 -D HORIZONTAL FORCE FACTORS BASED ON RATING CLASSIFICATION RATING CLASSIFICATION ZIC /R, I 0.183 II 0.138 III & IV 0.110 2C TABLE NO 8.08 -E HORIZONTAL FORCE FACTORS "ZI" FOR PARTS OR PORTIONS OF STRUCTURES RATING CLASSIFICATION ZI I 1.50 II 1.00 III & IV 0.75 TABLE NO 8.08 -F HORIZONTAL FORCE FACTOR "Cp" FOR PARTS OR PORTIONS OF BUILDINGS OR OTHER STRUCTURES (1) Part or Portion of _ Direction Value Buildings of force of CF, Exterior bearing and non - bearing galls, interior bearing walls and partit Dns„ interior non - bearing walls and partitions over ten feet in heigh?, Normal to masonry fences over six feet in height Flat surface 0.20 Cantilever parapet and other cantilever Normal to walls, except retaining walls. flat surface 1.00 Exterior and interior ornamentatit -ns Any and appendages Direction 1.00 When connected to or a part of —a building; towers, tanks, towers aid tanks plus contents, racks over 8 Feet. 3 inches in height plus contents, Any chimneys, smokestacks, and penthoises. Direction When connected to or a part of a building: Rigid and rigidly mounter equipment and machinery not requiaed for continued operation of essenr.�:i1 occupancies. (5) Tanks plus effective contents rentIng on the ground. 21 Any Horizontal Direction Any Direction 0.20 (2) (4) 0.20 (3) 0.12 Floors and roofs acting as diaphragms. Prefabricated structural elements — other than walls, with force applied at center of gravity of assembly. Connections for exterior panels o elements. Footnotes to Table No. 8.08 -F (1) See Section 8.08.160(b) for u.se of C,,. In the plane of the diaphragm 0.12 (6) Any Horizontal Direction 0.30 Any Direction 2.00 (2) When located in the upper port "ion of any building with a Hn /D ration of 5 to 1 or greater the value shall be increased by 50 %. (3) For flexible and flexibly mounted equipment and machinery, the appropriate values for C,, shall be determined with considera- tion given to both the dynamic: properties of the equipment and machinery and to the building or ;tructure in which it is placed. (4) The Wp for storage racks shall be the weight of the racks Plus contents. The value of Cp or racks over two storage sup- port levels in height shall be 0 16 for the levels below the top two levels. (5) The design of the equipment and machinery and their anchorage is an integral part of the design and specification of such equipment and machinery. The structure to which the equipment or machinery is mounted shall be capable of resisting the anchorage forces (see also Section 2312(8)4 (6) Floor and roofs acting as diaphragms shall be designed for a minimum force resulting from a CF of .12 applied to WV unless a greater force results from the distribution of lateral forces in accordance with Section 2312. 22 TABLE NO. 8.08 - +3 ALLOWABLE VALUE OF HEIGHT - THICKNESS RATIO OF UNREINFORCED MASONRY WALLS WITH MINIMUM QUALITY MORTAR (1 (2) BUILDING WITH CROSSWALLS AS ALL OTHER DEFINED BY tiECTION 8803 BUILDINGS Walls of one story buildings 13 First story wall of multi -story buildings 15 Walls in top story of multi -story buildings g All other walls 13 (1) Minimum quality mortar sha.1 be determined by laboratory testing in accordance with Sect:ic- 8 08.170(e). (2) Table 8.08 -G is not applic:abie to buildings of rating clas- sification I. Walls of buildings within rating classification I shall be analyzed in accordance with Section 8.08.160(f). (3) The minimum mortar shear strengths required in following footnotes 4 and 5 shall be that; shear strength without the effect of axial stress in the wall at the point of the test. (4) The larger height -to- thickness ratio may be used where mor- tar shear tests in accordance with Section 8.08.170(a)3 establish a minimum mortar shear strength of not less than 100 psi or where the tested mortar shear strength is not: less than 60 psi and a visual examination of the vertical wythe -to -wythe wall joint (collar joint) indicates net ess 'than 50 percent mortar coverage. (5) Where a visual examination of the cellar joint indicates not less than 50 percent mortar coverage and the minimum mortar shear strength when established in accordance with Section 8.08.170(a)3 is greater than 30 psi but less than 60 psi, the allowable height -to- thickness ratio may be determined by linear interpola- tion between the larger and sma'.er ratios in direct proportion to the mortar shear strength. 2 TABLE NO 8.08 -11 VALUES FOR EXISTING MATERIALS EXISTING MATERIALS OR CONFIGURATION OF MATERIALS (1) 1. HORIZONTAL DIAPHRAGMS a. Roofs with straight sheathing and roofing applied directly to the sheathing. 3. 4. 5. 6. b. Roofs with diagonal sheathing and roofing applied directly to the sheathing. c. Floors with straight tongue and groove sheathing d. Floors with straight sheathing and finished wood flooring. e. Floors with diagonal sheathing and finished wood flooring. f. Floors or roofs with straight sheathing and plaster applied to the joist or rafters. (2) SHEAR WALLS Wood stud walls with lath and plaster PLAIN CONCRETE FOOTINGS DOUGLAS FIR WOOD REINFORCING STEEL Structural Steel 24 ALLOWABLE VALUES 1.00lbs. per foot for :Seismic shear. 400lbs. per foot for seismic shear a..50lbs. per foot for siesmic shear. 300lbs. per foot for seismic shear. 450lbs per foot for seismic shear. Add 50lbs per foor to the allowable values for Items la and 1c. 100lbs. per foot each side for siesmic shear. f' =1500 psi unless c :otherwise shown by tests. Allowable stress same as No. 1 D.F. (3) ft18,000lbs. per square inch maximum. (3) ft20,000lbs per square J.nch maximum (1) Material must be sound and in good condition. (2) The wood lath and plaster must be reattached to existing joists or rafters in a manner appaoved by the Department. (3) Stresses given may be inceas,�d for combinations of loads as specified in Section 8.08.160((1)2 25 TABLE NO 8.08 -1 ALLOWABLE VALUES OF° NEW MATERIALS USED IN CONJUNCTION WITH EXISTING CONSTRUCTION (1) NEW MATERIALS OR CONFIGURATION OF MATERIALS 1. HORIZONTAL DIAPHRAGMS Plywood sheathing applied directly over existing straight. sheathing with ends of plywood sheets bearing on joists or rafters and edges of plywood located on center of individual sheathing boards. 2. SHEAR WALLS a. Plywood sheathing applied directly over existing wood studs. No value shall be given to plywood applied over existing plaster or wood sheathing. b. Dry wall or plaster applied directly over existing wood studs c. Dry wall or plaster applied to plywood sheathing over existing wood studs. 3. SHEAR BOLTS Shear bolts and shear dowels embedded a minimum of 8 inches into unreinforced masonry walls. Bolt centered in a 2 1/2 inch diameter hole with dry -pack or non - shrink grout around cir- cumference of bolt or dowel. (3) ALLOWABLE VALUES Same as specified in table No. 25 -J of this Code for blocked diaphragms.* Same as values specified in Table No. 25 -K for shear walls. 7'5 per cent of the value specified in Table No.47 -I 33 1/3 per cent of the values specified in Table No. 47 -I. 1.00 percent of the values for solid masonry specified in Table No. 24 -E. No values larger than those given for 3/4 inch bolts shall be used. * All tables that do not carry 1 8.08 number are found in the Uniform Building Code, 1988 editirn, 26 4. TENSION BOLTS Tension bolts and tension dowels 1200 lbs. per bolt or extending entirely through dowel. unreinforced masonry walls secured with bearing plates on far side of wall with at least 30 sq. inches of area. (2) (3) 5. WALL ANCHORS [8.08.170(b)l.l a. Bolts extending to the exterio 600 lbs. per bolt for. face of the wall with a 2 1/2 tension4see Item 3 inch round plate under the head. hshear bolts) for shear Installed as specified for shear values. bolts. Spaced not closer than 12 inches on centers. (1) (2) b. Bolts or dowels extending to the 1200 lbs. per bolt exterior face of the wall with or dowel for tension4. a 2 1/2 inch round plate under th- See Item 3 (shear Bolts) head and drill at an angle of or shear values. 22 1/2 degrees to the horizontal Installed as specified for shear bolts. (1) (2) c. Through bolt with bearing platy See Item 4(tension bolts) for tension per Item 4. Combined for tension values4. see with minimum 8 -inch grouted Item 3 (shear bolts) for section for shear per Item 3. shear values. 6. INFILLED WALLS Reinforced masonry infilled Same as values specified openings in existing unrein- for unreinforced masonry forced masonry walls with walls. keys or dowels to match reinforcing. 7. REINFORCED MASONRY Masonry piers and walls Same values as determined reinforced per Sections 2406,. per Section 2406. 2407 and 2409 8. REINFORCED CONCRETE Concrete footings, walls and Same values as specified piers reinforced as specified in Chapter 26 UBC. in Chapter 26 and designed for tributary loads. 27 9. EXISTING FOUNDATION LOADS Foundation loads for structures exhibiting no evidence of settlement. NOTES: Calculated existing foundation loads due to maximum dead load plus live load may be increased 50% for dead load plus seismic load required by this Division. (1) Bolts and dowels to be tested as specified in Section 8.08.170(f). (2) Bolts and dowels to be 1/2 in .h minimum in diameter. (3) Drilling for bolts and dowels shall be done with an electric rotary drill. Impact tools shall not bE� used for drilling holes or tightening anchor and shear bc'.t nuts (4) Allowable bolt and dowel values specified are for installa- tions in minimum three (3) wythe walls. For installations in two (2) wythe walls, use 50 percent of the value specified, except that no value shall be given to tension bolts that do not extend entirely through the wall and arf, secured with bearing plates on the far side. 28 TABLE NO 8.08 -J ALLOWABLE SHEAR STRESS FOR TESTED UNREINFORCED MASONRY WALLS Eighty percent Average tes!: results Seismic in -plane of test results of cores :, psi shear based on in psi not less gross area (1) than 30 plus axial stress 2C) 3 psi 40 plus axial stress 2� 4 psi 50 plus axial stress 3? 5 psi 100 plus axial stress t;', :>r more 100 psi max or more. (1) Allowable shear stress may be increased by addition of 10% of the axial stress due to the we_igrr:. of the wall directly above. 2L TABLE NO 8.08 -F; VALUES FOR EXISTING MA'T'ERIALS EXISTING MATERIALS OR CONFIGURATION OF MATERIALS' ------------------------ - - - - -- 1. HORIZONTAL DIAPHRAGMS a. Roofs with straight sheathing and roofing applied directly to the sheathing. b. Roofs with diagonal sheathing and roofing applied directly to the sheathing. 2. CROSSWALLS2 a. Plaster on wood or metal . lath. b. Plaster on gypsum lath. c. Gypsum wall board, unlocked edges. ALLOWALBE VALUES 100 lbs. per foot for seismic shear 250 lbs. per foot for seismic shear per side: 200 lbs, per foot for seismic shear. 1 715 lbs. per foot for seismic shear 75 lbs. per foot for seismic shear d. Gypsum wall board, 25 lbs. per foot for seismic blocked edges. ----------------------------------- ------- ...----------------------- 1Materials must be sound and in good condition. 2For corsswalls, values of all materials may be combined, except the total combined value shall not exceed 300 lbs. per foot for seismic, shear. 3C TABLE NO 8.08 -L ALLOWABLE VALUES OF NEW MATERIALS USED IN CONJUNCTION WITH EXISTING CONSTRUCTION NEW MATERIALS OR CONFIGURATION OF NEW AND EXISTING MATERIALS' ------------------------------ 1. HORIZONTAL DIAPHRAGMS Plywood sheathing applied directly over existing straight sheathing with ends of plywood sheets bearing on joists or rafters and edges of plywood located on center- of individual sheathing boards. 2. CROSSWALLS2 a. Plywood sheathing applied directly over existing wood studs. No value shall be given to ply- wood applied over exist- ing plaster or wood sheathing. b. Drywall or plaster applied directly over existing wood studs. ALLOWABLE VALUES 225 lbs. per foot for seismic shear 1.33 times the values specified in Table No. 25 -K for shear walls. 100 percent of the values specified in Table No. 47 -r. ------------------------------------------ ------------------------ 1Materials must be sound and in good condition. 'For crosswalls, values of all materials may be combined, except the total combined value shill not exceed 300 lbs. per foot for seismic shear. .3'.. C = Cp = D = f' _ G Fp = ft = hn = I = V = W = W 3 Z = GLOSSARY OF SYMBOLS ANI.) NOTATIONS Numerical coefficient a specified in Section 23122(d) Numerical coefficient a,� specified in Section 2312(g) and as set forth in Table No 1.3 -J The dimension of the structure in feet, in a direction parallel to the applied forces Specified compressive s°rength of concrete, psi Lateral forces on a parr, of the structure and in the direction under conside 'at :.on. Allowable tensile stres , psi Height in feet above th- base to level n Occupancy Importance Factor as set forth in Table No. 23 -K and modified. it Table 8.08 -A The total lateral force or shear at the base The total dead load as iefined in Section 2302 including the partition loading specified in Section 2304(d) where applicable The weight of a portion of a structure or nonstructural component Numerical coefficient dependent upon the zone as determined by Figure No 1, of Chapter 23. All areas in California are classified in Zones 3 or 4. For locations in Zone No.3, Z= 0.30 For locations in Zone No. 4, Z =0.40 ( See tab], no, 2 3 -1 . ) 3 w W x 2 a o. N r v x CL a c FIGURE 110. 3.08 -A 540 C) REGION OF DEMAND- CAPACITY RATIO3 WHERE CROSSWALLS 480 MAY BE USED TO INCREASE H/T RATIOS O2i REGION OF DEMAND- CAPACITY 420 RATIOS WHERE N/T RATIOS OF F "WITH CROSSWALLS" MAY BE USED O 4 3W_ �3 REGION OF DEMAHO- CAPACITY RATIOS WHERE H/T RATIOS OF "ALL OTHER BUILDINGS" SHALL BE USED 300 -- 240 180 120 o X 60 Q 0 I 0 1 2 I 4 5 6 DEMAND- CAIPACITY RATIO, 0.33WDI (2vuD) OR 0.33WD/ (2vQD ♦ Q) ACCEPTABLE SPAN COR DIAPBRAG.MS (HASID ON DISPLACZ.XMIT CONTROL CONCSPTy) 32 Section 3. SEVERABILITY. it any section, subsection, sen- tence, clause, phrase or word of 'his Ordinance is for any reason held to be invalid by a 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 passed and adopted this Ordinance and each and all provisions thereof, irrespective cf the fact that any one or more of said provisions may be declarec invalid. Section 4. The City Clerk shall certify to the passage and adoption of this ordinance by not "Less than a four - fifths vote of the City Council; shall enter thE:! same in the book of original ordinances of said City; shall mike a minute of the passage and adoption thereof in the records )f the proceedings of the City Council at which the same is passed and adopted; and shall, within fifteen (15) days after the passage and adoption thereof, cause the same to be published :in 'he manner prescribed by law. 1989 PASSED AND ADOPTEt: hLs day of ATTEST: City Clerk Maycr of the City of Moorpark, California