HomeMy WebLinkAboutOrdinance No. 2280 ORDINANCE NO. 2280
AN ORDINANCE OF THE CITY COUNCIL OF THE CITY OF
AZUSA ADDING SECTION 15.04.180 TO THE AZUSA
MUNICIPAL CODE REPEALING CHAPTER 96 OF THE COUNTY
OF LOS ANGELES BUILDING CODE RELATING TO
"POTENTIALLY EARTHQUAKE HAZARDOUS BUILDINGS" AND
ADDING CHAPTER 15.10 TO THE AZUSA MUNICIPAL CODE
ENTITLED "EARTHQUAKE HAZARD REDUCTION IN EXISTING
BUILDINGS"
THE CITY COUNCIL OF THE CITY OF AZUSA DOES ORDAIN
AS FOLLOWS:
SECTION 1. Section 15.04.180 is hereby added to
the Azusa Municipal Code to read as follows:
"15.04.180 BUILDING CODE - REPEAL OF CHAPTER 96,
EARTHQUAKE HAZARDS. The Building Code is amended
by deleting therefrom Chapter 96, 'Potentially
Earthquake Hazardous Buildings. '
SECTION 2 . Chapter 15. 10 entitled "Earthquake
Hazard Reduction in Existing Buildings" is hereby added to
the Azusa Municipal Code to read as follows:
"15. 10. 010 PURPOSE. The purpose of this Chapter
is to promote public safety and welfare by reducing
the risk of death or injury that may result from
the effects of earthquakes on unreinforced masonry
bearing wall buildings constructed before 1934 .
Such buildings have been widely recognized for
their sustaining of life hazardous damage as a
result of partial or complete collapse during past
moderate to strong earthquakes. This is
particularly important in Azusa where many
buildings are of the pre-1934 type.
"The provisions of this Chapter are minimum
standards for structural seismic resistance
established primarily to reduce the risk of life
loss or injury and will not necessarily prevent
loss of life or injury or prevent earthquake damage
to an existing building which complies with these
standards. This Chapter shall not require existing
electrical, plumbing, mechancial or fire safety
systems to be altered unless they constitute 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
buildings are required to be structurally analyzed
and anchored. Where the analysis determines
deficiencies, this Chapter requires the building to
be strengthened or demolished.
"The provisions of the State Historical Building
Code (SHBC) established under Part 8, Title 24 of
the California Administrative Code are incorporated
in this Chapter .
"15.10. 020 SCOPE. The provisions of the Chapter
shall apply to all buildings constructed or under
construction prior to October 6, 1933, or for which
a building permit was issued prior to October 6,
1933, which on the effective date of this ordinance
have unreinforced masonry bearing walls as defined
herein. This Chapter shall not apply to detached
one or two family dwellings and detached apartment
houses containing less than five dwelling units and
used solely for residential purposes.
"15.10 . 030 DEFINITIONS. For purposes of this
Chapter the applicable definitions in Sections 2302
and 2312, Building Code, and the following shall
apply:
"A. Building Code means the County of Los Angeles
Building Code, 1984 Edition, adopted pursuant to
Chapter 15.04 of this Code.
"B. Essential Building: Any building housing a
hospital or other medical facility having surgery
or emergency treatment areas; fire or police
stations; municipal government disaster operation
and communication centers.
"C. High Risk Building: Any building, not
classified an essential building, having an
occupant load as determined by Building Code
Section 3302 of 100 occupants or more.
Exception: A high-risk building 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
Official, for less than 20 hours per
week .
"D. Historical Building: Any building designated
as an historical building by an appropriate
Federal, State or City jurisdiction.
"E. Low-Risk Building: Any building, not
classified an essential building, having an
occupant load as determined by Building Code
Section 3302 of less than 20 occupants.
"F. Medium-Risk Building: Any building, not
classified as a high-risk building or an essential
building, having an occupant load as determined by
Building Code Section 3302 of 20 occupants or more.
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"G. 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 Building
Code Section 2417 ( j ) 3.
"15 . 10 .040 RATING CLASSIFICATIONS. The rating
classifications as exhibited in the Table No. A are
hereby established and each building within the
scope of this Chapter shall be placed in one such
rating classification by the Building Official.
The total occupant load of the entire building as
determined by Building Code Section 3302 shall be
used to determine the rating classification.
Exception: For the purpose of this Chapter,
portions of building constructed to act
independently when resisting seismic forces
may be placed in separate rating
classifications.
"15. 10 . 050 ADMINISTRATION.
A. Service of Order - Building Official shall
issue an order, as provided in Section 15. 10 . 050 B,
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 No. C. The minimum time period for the
service of such orders shall be measured from the
effective date of this Chapter . The Building
Official shall upon receipt of a written request
from the owner, order a building to comply with
this Chapter prior to the normal 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 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
Building Official to be within the scope of this
Chapter and, therefore, is required to meet the
minimum seismic standards of this Chapter . The
order shall specify the rating classification of
the building and shall be accompanied by a copy of
this Chapter which sets forth the owner ' s
alternatives and time limits for compliance.
C. Appeal From Order - The owner or person in
charge or control of the building may appeal the
Building Official ' s initial determination that the
building is within the scope of this Chapter to the
City Administrator or his designee. Such appeal
shall be filed with the Building Official within 30
days from the service date of the order described
• in Section 15. 10.050.B. Any such appeal shall be
decided by the City Administrator or his designee,
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not later than 60 days after the date that the
appeal is filed. Such appeal shall be made in
writing upon appropriate forms provided therefor by
the Building Official, and the grounds thereof
shall be stated clearly and concisely. Each appeal
to the City Administrator shall be accompanied by a
filing fee as set by resolution of the City
Council. Within 10 days after issuance of the
decision of the City Administrator or his designee,
the owner or person in charge or control may appeal
that decision to the City Council. Such appeal
shall be made in writing upon appropriate forms
provided therefor by the City Clerk and the grounds
thereof shall be stated clearly and concisely.
Each appeal to the City Council shall be filed with
the city Clerk and shall be accompanied by a filing
fee as set by resolution of the City Council.
D. Recordation - At the time the Building
Official serves the aforementioned order, 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
15.10, Earthquake Hazard Reduction in Existing
Buildings - of the Azusa Municipal Code. The
certificate shall also state that the owner thereof
has been ordered to structurally analyze the
building and to structurally alter or demolish it
where compliance with Chapter 15.10 is not
exhibited.
E. Termination of Status - If the building is
either demolished, found not to be within the scope
of this Chapter, or is structurally capable of
resisting minimum seismic forces required by this
Chapter as a result of structural alterations or an
analysis, the Building Official shall file with the
Office of the County Recorder a certificate
terminating the status of the subject building as
being classified within the scope of this Chapter .
F. Enforcement - If the owner or other person in
charge or control of the subject building fails to
comply with any order issued by the Building
Official pursuant to this Chapter within any of the
time limits set forth in Section 15. 10 . 060, the
Building Official shall order that the entire
building be vacated and that the building 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 such
additional time as may have been granted by the
Community Development Director or his designee, the
Building Official may order its demolition in
accordance with the provisions of Chapter 15 .08 of
this Code.
"15.10.060 GENERAL REQUIREMENTS.
A. The owner of each building within the scope of
this Chapter shall cause a structural analysis to
be made of the building by a civil or structural
engineer or architect licensed by the State of
California and, if the building does not meet the
minimum earthquake standards specified in this
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Chapter, the owner shall cause it to be
structurally altered to conform to such standards
or cause the building to be demolished.
B. 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 within the stated time limits:
1 . Within 270 days after the service of the
order described in Section 15 .10.050, a
structural analysis. Such analysis which is
subject to approval of the Building Official,
shall demonstrate that the building meets the
minimum requirements of this Chapter ; or
2. Within 270 days after the service of said
order, the structural analysis and plans for
the proposed structural alterations of the
building necessary to comply to the minimum
requirements of this Chapter; or
3. Within 120 days after service of said
order, plans for the installation of wall
anchors in accordance with the requirements
specified in Section 15.10. 080; or
4. Within 270 days after the service of the
order , plans for the demolition of the
building.
C. After the 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. B. These time limits shall
begin to run from the date the order is served in
accordance with Sections 15.10.050 A and B.
D. Owners electing to comply with Subsection 3 of
Section 15.10.060 B. are also required to comply
with Subsections 2 or 4 of Section 15.10.060 B.
provided, however, that the 270-day period provided
for in such Subsections 2 and 4 and the time limits
for obtaining a building permit, commencing
construction and completing construction for
complete structural alterations or building
demolition set forth in Table No. B shall be
extended in accordance with Table No. 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 accordance with Section
15.10 .050 B. The time limit for commencing
construction shall commence to run from the date
the building permit is issued.
"15. 10 .070 HISTORICAL BUILDINGS.
A. General - The standards and procedures
established by this Chapter shall apply in all
respects to an historical building (as defined in
the State Historic Building Code) except that as a
means to preserve original architectural elements
and facilitate restoration, a historical building
may, in addition, comply with the special
provisions set forth in this Section.
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B. Unburned Clay Masonry or Adobe - Existing or
reerected walls of adobe construction shall conform
to the following:
1. Unreinforced adobe masonry walls shall
not exceed a height or length to thickness
ratio of 5, for exterior bearing walls and
must be provided with a reinforced bond beam
at the top, interconnecting all walls.
Minimum beam depth shall be 6 inches and a
minimum width of 8 inches less than the wall
width. Minimum wall thickness shall be 18
inches for exterior bearing walls and 10
inches for adobe partitions. No adobe
structure shall exceed one story in height
unless the historic evidence indicates a two-
story height . In such cases the height to
thickness ratio shall be the same as above for
the first floor based on the total two-story
height and the second floor wall thickness
shall not exceed the ratio 5 by more than 20
percent. Bond beams shall be provided at the
roof and second floor levels.
2. Foundation footings shall be reinforced
concrete under newly reconstructed walls and
shall be 50 percent wider than the wall above,
soil conditions permitting, except that the
foundation wall may be 4 inches less in width
than the wall above if a rockburned brick, or
stabilized adobe facing is necessary to
provide authenticity.
3. New or existing unstabilized brick and
adobe brick masonry shall have an average
compressive strength of 225 pounds per square
inch when tested in accordance with ASTM
designation C67 . One sample out of five may
have a compressive strength of not less than
188 pounds per square inch. Unstabilized
brick may be used where existing bricks are
unstabilized and where the building is not
susceptible to flooding conditions or direct
exposure. Adobe may be allowed a maximum
value of 3 pounds per square inch for shear
with no increase for lateral forces.
4. Mortar may be of the same soil
composition and stabilization as the brick in
lieu of cement mortar .
5. Nominal tension stresses due to seismic
forces normal to the wall may be neglected if
the wall meets thickness requirements and
shear values allowed by this subsection.
C. Archaic Materials - Allowable stresses for
archaic materials not specified in the Building
Code shall be based on substantiating research data
or engineering judgment subject to the Building
Official ' s satisfaction.
D. Alternative Materials and SHBC Advisory Review
Alternative materials, design or methods of
construction will be considered as set forth in
Section 15.10 . 090 . In addition, when a request for
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an alternative proposed design, material or method
of construction is being considered, the Building
Official may file a written request for opinion to
the State Historical Building Code Advisory Board
for its consideration, advice or findings in
accordance with SHBC.
"15.10 .080 ANALYSIS AND DESIGN.
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 nonconcurrently in the direction of each of
the main axis of the structure in accordance with
the following equation:
V=IKCSW FORMULA (8-1)
The value of IKCS need not exceed the values set
forth in Table No. 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 A of this Section and Building Code
Section 3212 (d) , but not less than the value from
the following equation:
Fp- ICp SWp FORMULA (8-2)
For the provisions of this Subsection, the product
of IS need not exceed the values as set forth in
Table No. E.
Exception: Unreinforced masonry walls in buildings
not having a rating classification of I may be
analyzed in accordance with Section 15.10.090.
C. Anchorage and Interconnection - Anchorage and
interconnection of all parts, portions and elements
of the structure shall be analyzed and designed for
lateral forces in accordance with the equation Fp-
ICp SWp (8-2) as modified by Table No. E. Minimum
anchorage of masonry walls to each floor or roof
shall resist a minimum force of 200 pounds per
linear foot acting normal to 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 Building Code unless
specifically provided for in this Chapter .
E. Required Analysis -
1. General. Except as modified herein, 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 specified in Building Code
Chapter 23.
2. Continuous Stress Path. A complete,
continuous stress path from every part or
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portion of the structure to the ground shall
be provided for the required horizontal
forces.
3. Positive Connections. All parts,
portions or elements of the structure shall be
interconnected by positive means.
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 conform to
those permitted by the Building Code, and
those materials and types of construction
specified in Section 15. 10.090.
2. Connections. Materials and connectors
used for interconnection of parts and portions
of the structure shall conform to the Building
Code.
3 . Unreinforced Masonry Walls. Except as
modified herein, unreinforced masonry walls
shall be analyzed as specified in Sections
2416, 2418 and 2419 of the Building Code to
withstand all vertical loads as specified in
Chapter 23 of the Building Code, in addition
to the seismic forces required by this
Chapter . The 50 percent increase in the
seismic force factor for shear walls as
specified in Table No. 24-H of the Building
Code may be omitted in the computation of
seismic loads to existing shear walls. No
allowable tension stress will be permitted in
unreinforced masonry walls. Walls not capable
of resisting the required design forces
specified in this Chapter shall be
strengthened or shall be removed and replaced.
Exceptions:
a. Unreinforced masonry walls in
buildings not classified as a Rating
Classification I pursuant to Table No. A
may be analyzed in accordance with
Section 15.10. 090.
b. Unreinforced masonry walls which
carry no design loads other than its own
weight may be considered as veneer if
they are adequately anchored 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 combined vertical and horizontal
forces shall comply with Section 2312 ( j ) 2 of
the Building Code.
2. Existing Materials. When stress in
existing lateral force resisting elements are
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due to a combination of dead loads plus live
loads plus seismic loads, the allowable
working stress specified in the Building Code
may be increased 100 percent. However, no
increase will be permitted in the stresses
allowed in Section 15. 10.090 and the stresses
in members due only to seismic and dead loads
shall not exceed the values permitted by
Section 2303(d) of the Building Code.
"15.10 .090 MATERIALS OF CONSTRUCTION.
A. General - All materials permitted by the
Building Code, including their appropriate
allowable stresses and those existing
configurations of materials specified herein may be
utilized to meet the requirements of this Chapter .
B. Existing Materials -
1. a. Unreinforced Masonry Walls.
Unreinforced masonry walls analyzed in
accordance with this Section may provide
vertical support for roof and floor
construction and resistance to lateral
loads . The bonding of such walls shall be
specified in Section 2412(b) 1 of the Building
Code.
b. Tension stresses due to seismic
forces normal to the wall may be neglected if
the wall does not exceed the height or length
to thickness ratio and the in-place shear
stresses due to seismic loads as set forth in
Tables No. F and I .
c. If the wall height-thickness ratio
exceeds the specified limits, the wall may be
supported by vertical bracing members designed
in accordance with Section 15.10 .080 F. The
deflection of such bracing member 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 Section 15. 10 .080B if the
deflection at design loads is not less than
one-quarter nor more than one-third of the
wall thickness .
d. All vertical bracing members shall
be attached to floor and roof construction 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.
e. The wall height may be measured
vertically 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 displacements
of the floor or roof.
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2. Existing Roof, Floors, Walls, Footings,
and Wood Framing. Existing materials including
wood shear walls utilized in the described
configuration 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 No. G.
C. Strengthening of Existing Materials. New
materials including wood shear walls may be
utilized to strengthen portions of the existing
seismic resisting system in the described
configurations provided that the stresses do not
exceed the values shown in Table H.
D. Alternate Materials. Alternate materials,
designs and methods of construction may be approved
by the Building Official in accordance with the
provisions of Section 105, Building Code.
E. Minimum Acceptable Quality of 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
replaced by new materials . The quality of
mortar in all masonry walls shall be
determined by performing in-place shear tests
or by testing eight-inch diameter cores .
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 tests 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 masonry
cements shall not be used. All preparation
and mortar pointing shall be done under the
continuous inspection of a Registered Deputy
Building Inspector . At the conclusion of the
inspection, the inspector shall submit a
written report to the licensed engineer or
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 a testing agency approved by the
Building Official. An accurate record of all
such tests and their location in the building
shall be recorded 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 two per wall
or line of wall elements resisting a common
force, or 1 per 1500 square feet of wall
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surface, with a minimum of eight tests in any
case. The exact test or core location shall be
determined at the building site by the
licensed engineer or architect responsible for
the seismic analysis of the subject building.
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. The minimum quality mortar
in 80 percent of the shear tests shall not be
less than the total of 30 psi plus the axial
stress in the wall at the point of the test.
The shear stress shall be based on the gross
area of both bed joints and shall be that at
which movement of the brick is first observed.
4. Core Tests. A minimum number of mortar
test specimens equal to the number of required
cores 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 placing the circular
core section in a compression testing machine
with the mortar bed joint rotated 15 degrees
from the axis of the applied loan. The mortar
joint tested in shear shall have an average
ultimate stress based on 20 psi based on the
gross area. The average shall be obtained
from the 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-fourth of all new
shear bolts and dowels embedded in unreinforced
masonry walls shall be tested by a Registered
Deputy Building Inspector using a torque calibrated
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 or dowels = 60 foot-lbs
No bolts exceeding 3/4" shall be used. All nuts
shall be installed over malleable iron or plate
washers when bearing on wood and heavy cut washers
when bearing on stell.
G Determination of Allowable Stresses for Design
Methods Based on Test Results.
1. Design Shear Values. Design seismic in-
place shear stresses shall be substantiated by
tests performed as specified in Subsections E.
3 and 4 . Design stresses shall be related to
test results obtained in accordance with Table
No. I . Intermediate values between 3 and 10
psi may be interpolated.
2 . Design Compression and Tension Values.
Compression stresses for unreinforced masonry
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having a minimum design shear value of 3 psi
shall not exceed 100 psi . Design tension
values for unreinforced masonry shall not 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 walls
with joists 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. The rod anchor shall be given a
preload of 300 lbs . prior to establishing a datum
for recording elongation. The tension test load
reported shall be 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 forty 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 enlarged 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 resistance value assigned the device
shall be twenty percent of the average of the
ultimate loans.
15.10 .100 INFORMATION REQUIRED ON PLANS.
A. General. In addition to the seismic analysis
required elsewhere in this Chapter, the licensed
engineer or architect responsible for the seismic
analysis of the building shall determine and record
the information required by this Section on the
approved plans.
B. Construction Details. The following
requirements with appropriate construction details
shall be made part of the approved plans:
1. a. All unreinforced masonry walls shall
be anchored at the roof level by tension bolts
through the wall as specified in Table H, or
by approved equivalent at a maximum anchor
spacing of six feet.
b. All unreinforced masonry walls shall
be anchored at all floors with tension bolts
through the wall or by existing rod anchors at
a 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 required
shall conform to Section 15 .10.090 H.
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c. When access to the exterior face of
the masonry wall is prevented by proximity of
an existing building, wall anchors conforming
to 5 and 6 in Table H may be used.
d. Alternative devices to be used in
lieu of tension bolts for masonry wall
anchorage shall be tested as specified in
Section 15. 10.090 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 other than
rafters or joints are supported on masonry,
ledgers or columns shall be installed to
support vertical loads of the roof or floor
members.
4. Parapets and exterior wall appendages not
capable of resisting the forces specified in
this Chapter shall be removed, stabilized or
braced to insure that the parapets and
appendages remain in their original position.
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 shall be done under the
continuous inspection of a Registered Deputy
Building Inspector certified to inspect
masonry or concrete. At the conclusion of the
project, the inspector shall submit a written
report to the Building Official setting forth
the portion of work inspected.
6. Repair details of any cracked or damaged
unreinforced masonry wall required to resist
forces specified in this Chapter.
C. Existing Construction. The following existing
construction information shall be made part of the
approved plans.
1 . The type and dimensions of existing walls
and the size and spacing of floor and roof
members.
2 . The extent and type of existing wall
anchorage to floors and roof.
3. Accurately dimensioned floor plans and
masonry wall elevations showing dimensioned
openings, piers, wall thickness and heights.
4 . The location of cracks or damaged
portions of unreinforced masonry walls
requiring repairs.
5. The type of interior wall surfaces and if
reinstalling or anchoring of ceiling plaster
is necessary.
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6. The general condition of the mortar
joints and if the joints need pointing.
7 . The extent and type of parapet
corrections which were performed in accordance
with this ordinance.
TABLE NO. A
RATING CLASSIFICATIONS
TYPE OF BUILDING CLASSIFICATIONS
Essential Building I
High Risk Building II
Medium Risk Building III
Low Risk Building IV
TABLE NO. B
TIME LIMITS FOR COMPLIANCE
REQUIRED ACTION OBTAIN BUILDING COMMENCE COMPLETE
BY OWNER PERMIT CONSTRUCTION CONSTRUCTION
WITHIN WITHIN
Complete Structural 1 year 180 days* 3 years
Alterations or
Building Demolition
Wall Anchor
Installation 180 days 270 days 1 year
*Measured from date of building permit issuance
TABLE NO. C
SERVICE PRIORITIES AND EXTENDED TIME PROVISIONS
Rating Occupant Extension of Time Minimum Time
Classification Load if Wall Anchors Periods for
are installed Service of Order
I Any 1 year 0
(Highest Priority)
II 100 or more 3 years 90 days
100 or more 5 years 1 year
III More than 50,
but less than 6 years 2 years
100
More than 19, 6 years 3 years
but less than
51
IV Less than
(Lowest Priority) 20 7 years 4 years
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TABLE NO. D
HORIZONTAL FORCE FACTORS BASED
ON RATING CLASSIFICATION
RATING CLASSIFICATION IKCS
I 0 .186
II 0 .133
III & IV 0 .100
TABLE NO. E
HORIZONTAL FORCE FACTORS "IS"
FOR PARTS OR PORTIONS OF STRUCTURES
RATING CLASSIFICATION IS
I 1. 50
II 1 .00
III 0 .75
TABLE NO. F
ALLOWABLE VALUE OF HEIGHT-TRAINING RATIO
OF UNREINFORCED MASONRY WALLS WITH MAXIMUM
QUALITY MORTAR. ( 1) . ( 2) .
BUILDINGS WITH CROSS WALLS AS ALL OTHERS
DEFINED BY BUILDING CODE BUILDINGS
Walls of
One Story Building 16 13
First Story Wall of
Multi-Story Buildings 16 15
Walls in Top Story of
Multi-Story Buildings 14 9
All Other Walls 16 13
NOTES:
(1) Minimum quality mortar shall be determined by labratory
testing in accordance with Section 15 .10 . 090 E.
( 2) Table F is not applicable to buildings of rating
classification I . Walls of buildings within rating
classification I shall be analyzed in accordance with
Section 15 .10 . 080 F.
TABLE NO. G
VALUES FOR EXISTING MATERIALS
NEW MATERIALS OR ALLOWABLE VALUES
CONFIGURATION OF MATERIALS ( 1)
1. HORIZONTAL DIAPHRAGMS
a. Roofs with straight sheathing 100 lbs. per foot for
roofing applied directly and seismic shear .
to the sheathing.
b. Roofs with diagonal sheathing 400 lbs. per foot for
and roofing applied directly seismic shear .
to the sheathing.
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c. Floors with straight tongue 150 lbs. per foot for
and groove sheathing. seismic shear.
d. Floors with straight sheathing 300 lbs. per foot for
and finished wood flooring. seismic shear .
e. Floors with diagonal sheathing 450 lbs. per foot for
and finished wood flooring. seismic shear .
f. Floors or roofs with straight Add 50 lbs. per foot
sheathing and plaster applied to the allowable
to the joist or rafters. ( 2) . values for items l.a
and l.c.
2. SHEAR WALLS
a. Wood stud walls with lath 100 lbs. per foot
and plaster . each side for seismic
shear .
3. PLAIN CONCRETE FOOTINGS f ' =1500 psi unless
otherwise shown by
tests.
4 . DOUGLAS FIR WOOD Allowable stress same
as No. 1 D.F ( 3) .
5. REINFORCING STEEL ft=18,000 lbs. per
square inch maximum
( 3) .
6. STRUCTURAL STEEL ft=20,000 lbs. per
square inch maximum
( 3)
NOTES:
(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 approved by the Building
Official.
( 3) Stresses given may be increased for combinations of
loads as specified in Section 15. 10 080 G. 2 .
TABLE NO. H
ALLOWABLE VALUES OF NEW MATERIALS USED
IN CONJUNCTION WITH EXISTING CONSTRUCTION
NEW MATERIALS OR ALLOWABLE VALUES
CONFIGURATION OF MATERIALS
1. HORIZONTAL DIAPHRAGMS.
Plywood sheathing applies directly Same as specified in
over existing straight sheathing Table 25-J of Building
with ends of plywood sheets bearing Code for blocked
on joists or rafters and edges of diaphragms.
plywood located on center of in-
dividual sheathing boards.
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2. SHEAR WALLS.
a. Plywood sheathing applied Same as values
directly over existing wood specified in Building
studs. No value shall be given Code, Table 25-K
to plywood applied over existing for shear walls.
plaster or wood sheathing.
b. Dry wall or plaster applied 75 percent of the
directly over existing wood values specified in
studs. Building Code,
Table 47-I .
c. Dry wall or plaster 33 1/3 percent of the
applied to plywood sheathing values specified in
over existing wood studs. Building Code,
Table 47-I.
3. SHEAR BOLTS.
Shear bolts and shear dowels 100 percent of the
embedded a minimum of 8 inches values for masonry
into unreinforced masonry walls. specified in Building
Bolt centered in a 2 1/2 inch Code, Table No. 24-G.
diameter hole with dry-pack or No values larger than
non-shrink grout around circumfer- those given for 3/4
ence of bolt or dowel. (1) ( 3) inch bolts shall be
used.
4. TENSION BOLTS.
Tension bolts and tension dowels 1200 lbs. per bolt or
extending entirely through unrein- dowel.
forced masonry walls secured with
bearing plates on far side of wall
with at least 30 sq. inches of area.
( 2) ( 3)
5. WALL ANCHORS (9610 (b) 1) .
Bolts extending to the exterior 600 lbs. per bolt.
face of the wall with a 2 1/2
inch round plate under the head.
Install as specified for shear
bolts. Spaced not closer than
12 inches on centers ( 1) ( 2) ( 3) .
6. Bolts or dowels extending to 1200 lbs. per bolt or
the exterior face of the wall dowel.
with a 2 1/2 inch round plate
under the head and drill at an
angle of 22 1/2 degrees to the
horizontal. Installed as
specified for shear bolts. (1) ( 2)
( 3)
7 . INFILLED WALLS
Reinforced masonry infilled Same as values speci-
openings in existing unrein- fied for unreinforced
forced masonry walls with masonry walls .
keys or dowels to match
reinforcing.
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8. REINFORCED MASONRY.
Masonry piers and walls rein- Same as values
forced per Building Code specified in Building
Section 2417 Code Table No. 24-B.
9 . REINFORCED CONCRETE.
Concrete footings, walls and Same as values
piers reinforced as specified specified in Building
in Building Code Chapter 26, Code in Chapter 26.
and designed for tributary loans.
10 . EXISTING FOUNDATION LOADS.
Foundation loads for structures Calculated existing
exhibiting no evidence of foundation loads due
settlement. to maximum dead loan
plus live load may be
increased 25 percent
for dead loan, and
may be increased 50
percent for dead loan
plus seismic load
required by this
Chapter .
NOTES:
(1) Bolts and dowels to be tested as specified in Section
15.10 . 090 F.
( 2) Bolts and dowels to be 1/2 inch 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 bolt
nuts.
TABLE NO. I
ALLOWABLE SHEAR STRESS FOR TESTED
UNREINFORCED MASONRY WALLS
Eighty percent Average test results Seismic in-place
of test results of cores in psi shear based on
in psi not less gross area.
than
30 plus axial stress 20 3 psi*
40 plus axial stress 27 4 psi*
50 plus axial stress 33 5 psi*
100 plus axial stress
or more 67 or more 10 psi max*
*Allowable shear stress may be increased by addition of 10% of
the anial stress due to the weight of the wall directly above. "
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SECTION 2. The City Clerk shall certify to the adoption of
this ordinance, causing it to be published as required by law.
APPROVED, PASSED AND ADOPTED this 3rd day of September ,
1985.
fir ,
MAYOR
STATE OF CALIFORNIA )
ss.
COUNTY OF LOS ANGELES )
CITY OF AZUSA )
I, ADOLPH SOLIS, City Clerk of the City of Azusa, do hereby
certify that the foregoing Ordinance No. 2280 was
regularly introduced and placed upon its first reading at a
regular meeting of the City Council on the 19th day
of August , 1985. That thereafter, said Ordinance was duly
adopted and passed at a regular meeting of the City Council on
the 3rd day of September , 1985, by the following vote, to
wit :
AYES: COUNCILMEMBERS: CRUZ, COOK, CAMARENA, LATTA, MOSES
NOES: COUNCILMEMBERS: NONE
ABSENT: COUNCILMEMBERS: NONE
/7 ,/
CM CLERK
4
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