HomeMy WebLinkAboutAGENDA REPORT 1989 1206 CC REG ITEM 11IELOISE BROWN
Mayor
BERNARDO M. PEREZ
Mayor Pro Tern
CLINT HARPER, Ph. D.
Councilmember
PAUL LAWRASON
Councilmember
SCOTT MONTGOMERY
Councilmember
RICHARD T. HARE
City Treasurer
FROM:
DATE:
J ITEM / 1 MOORPARK ;03,a
M E M O R A N D U M
The Honorable City Council
Patrick J. Richards, Director. of Community
November 20, 1989
STEVEN KUENY
City Manager
CHERYL J. KANE
City Attorney
PATRICK RICHARDS, A.I.C.P.
Director of
Community Development
R. DENNIS DELZEIT
City Engineer
JOHN V. GILLESPIE
Chief of Police
Development
SUBJECT: ABATEMENT OF HAZARDOUS UNREINFORCED MASONRY BUILDINGS
Senate Bill 547 (see Exhibit "1 ") requires mitigation of hazards associated
with unreinforced masonry buildings in areas subject to earthquakes.
Unreinforced masonry buildings have been identified in the City of
Moorpark. A model ordinance is proposed which requires structural upgrade
of this type of potentially hazardous structure.
Back& ound
Widespread concerns over earthquake safety caused the state legislature to
pass SB547. This law requires every 1 <)cal jurisdiction in seismic zone 4
to identify all "potentially hazardous buildings" which are defined as
buildings that contain walls constructed of brick or other masonry
materials, and that are not reinforced. Such buildings, commonly called
"unreinforced masonry buildings" do not withstand earthquakes well, and
they have caused many injuries and deaths in large earthquakes.
Senate Bill 547 requires that local j1irisdicLions accomplish three tasks
prior to January 1, 1990:
Task One: Identify all URM buildings that are potentially
hazardous.
Task Two: Develop and impleme,it a mitigation program to reduce
the hazard.
Task Three: Submit information i)ri potentially hazardous buildings
and hazard mitigation programs to the Seismic Safety
Commission.
Task One Is complete. Staff has srrvoyed the City of Moorpark and
identified certain buildings as potentially hazardous. Council. direction
is sought in order to proceed will! Task Two; the development and
implementation of a mitigation program.
799 Moorpark Avenue Moorpark, California 93021 (805) 529 -6864
Dr r%r7,� r%^r4 /r%r.7A /T T
TO: The Honorable City Council
FROM: Patrick J. Richards, Director. of Community Development
DATE: November 20, 1989
SUBJECT: ABATEMENT OF HAZARDOUS UNREINFORCED MASONRY BUILDINGS
Page -2-
Exhibit "2" to this report is a summary of the completed survey of
unreinforced buildings. A total of seven (7) buildings have been
identified as partially or entirely unreinforced masonry and therefore
potentially hazardous. The structures of greatest concern are a church
and a theater which have high occupancy loads and are classified as high
risk buildings. The inclusion of the church on this list is based upon an
incomplete inspection. Staff continues to attempt to contact the
responsible individuals in order to gain access and complete the
inspection. If the owners of the church building fail to cooperate in the
completion of the survey inspection then it is recommended that they be
required to demonstrate the structural adequacy of the buildings under the
provisions of the proposed ordinance.
nicrnscinn
The continued use of unreinforced masonry buildings constitutes a
significant hazard to life safety. Mitigation of this hazard is necessary.
The State of California Seismic Safety Commission has developed a model
ordinance requiring earthquake hazard reduction in existing buildings.
This model ordinance is included as Exhibit "3" to this report.
Senate Bill 547 requires that the City develop and implement a mitigation
program to reduce the hazard. SB547 does not mandate any particular
mitigation program. Mitigation programs may involve a wide range of
measures. The proposed ordinance is one approach which requires engineered
structural upgrade of buildings in accordance with a risk classification
system.
Staff Recommended Action
Direct staff to draft an ordinance based upon the State Seismic Safety
Commission model ordinance requiring structural upgrade of unreinforced
masonry buildings.
MOORPARK, CALIFORNIA
City Council Meeting
of 1
ACTIO -A
By
IIr.nt, -c nnrr /nWd /D TO
i
Exhibit B
The URM Law
Senate Bill No. 547
EXHIBIT_____
CHAPTER 250
An act to add Chapter 12.2 (commencing with Section 8875) to
Division 1 of Title 2 of the Government Code, relating to seismic
safety, and making an appropriation therefor.
I Approved by Governor July 2, 1986. Filed with
Secretary of State July 3, 1986.1
LEGISLATIVE COUNSELS DIGEST
SB 547, Alquist. Seismic safety.
(1) Under existing law, the Seismic Safety Commission is
charged with the duty of establishing programs for earthquake
prediction and earthquake hazard mitigation and is required to
prepare the California Earthquake Hazard Reduction Program in
consultation with specified agencies and groups.
This bill would require the commission to initiate a program of
identifying potentially hazardous buildings, as defined, by
requiring local building departments of cities and counties by
January 1, 1990, to identify all those buildings within their
jurisdiction, to establish a mitigation program, as specified, and to
report to the commission. The bill would authorize local building
departments to establish a schedule of fees to recover the costs of
identifying potentially hazardous buildings and carrying out other
requirements of the bill. The bill would require the commission to
prepare an advisory report for local jurisdictions containing criteria
and procedures, as specified, by September 1, 1987. The duties
imposed on local governmental entities by this bill would be state -
mandated local programs, except as specified.
The bill would appropriate $150,000 to the commission for
preparation of the advisory report.
(2) The California Constitution requires the state to reimburse
local agencies and school districts for certain costs mandated by the
state. Statutory provisions establish procedures for making that
reimbursement.
This bill would provide that no reimbursement is required by this
act for a specified reason.
Appropriation: yes.
The people of the .State of California do enact as follows:
SECTION 1. (a) The Legislature recognizes that California is
situated in a seismically active region with earthquake faults which
subject large areas of the state to high seismic risk. The Legislature
further recognizes that the existence and occupancy of potentially
hazardous buildings constitute a severe threat to the public safety in
Exhibit B (continued)
The URM Law
Ch. 250 - 2 -
the event of an earthquake of moderate to high magnitude.
(b) The Legislature additionally finds that the Seismic Safety
Commission estimates that there may be more than 60,000
unreinforced masonry buildings constructed before 1933 which
remain in use in this state. As part of an effort to protect the public
health and safety, the Legislature declares the need to establish
programs in the seismically active areas of the state to identify
potentially hazardous buildings within local governmental
jurisdictions.
SEC. 2. Chapter 12.2 (commencing with Section 8875) is added
to Division 1 of Title 2 of the Government Code, to read:
CHAPTER 12.2 BUILDING EARTHQUAKE SAFETY
8875. Unless the context otherwise requires, the following
definitions shall govern the construction of this chapter:
(a) "Potentially hazardous building" means any building
constructed prior to the adoption of local building codes requiring
earthquake resistant design of buildings and constructed of
unreinforced masonry wall construction. "Potentially hazardous
building" includes all buildings of this type, including, but not
limited to, public and private schools, theaters, places of public
assembly, apartment buildings, hotels, motels, fire stations, police
stations, and buildings housing emergency services, equipment, or
supplies, such as government buildings, disaster relief centers,
communications facilities, hospitals, blood banks, pharmaceutical
supply warehouses• plants, and retail outlets. "Potentially
hazardous building" does not include warehouses or similar
structures not used for human habitation, except for warehouses or
,,tructures housing emergency services equipment or supplies.
"Potentially hazardous building" does not include any building
having five living units or less. "Potentially hazardous building"
does not include, for purposes of subdivision (a) of Section 8877,
any building which qualifies as "historical property" as determined
by an appropriate governmental agency under Section 37602 of the
Health and Safety Code.
(b) "Local building department" means a department or agency
of a city or county charged with the responsibility for the
enforcement of local building codes.
8876. A program is hereby established within all cities, both
general law and chartered, and all counties and portions thereof
located within seismic zone 4, as defined and illustrated in Chapter
2 -23 of Part 2 of Title 24 of the California Administrative Code, to
identify all potentially hazardous buildings and to establish a
program for mitigation of identified potentially hazardous
buildings.
By September 1, 1987, the Seismic Safety Commission, in
cooperation with the League of California Cities, the County
Supervisors Association, and California building officials, shall
prepare an advisory report for local jurisdictions containing criteria
Chapter 9 Reference Material 0
Exhibit B (continued)
The URM Law
-3- Ch. 250
and procedures for purposes of Section 8877.
8877. Local building departments shall do all of the following:
(a) Identify all potentially hazardous buildings within their
respective jurisdictions on or before January 1, 1990. This
identification shall include current building use and daily
occupancy load. In regard to identifying and inventorying the
buildings, the local building departments may establish a schedule
of fees to recover the costs of identifying potentially hazardous
buildings and carrying out this chapter.
(h) Establish a mitigation program for potentially hazardous
buildings to include notification to the legal owner that the building
is considered to be one of a general type of structure that historically
has exhibited little resistance to earthquake motion. The mitigation
program may include the adoption by ordinance of a hazardous
buildings program, measures to strengthen buildings, measures to
change the use to acceptable occupancy levels or to demolish the
building, tax incentives available for seismic rehabilitation, low -
cost seismic rehabilitation loans available under Division 32
(commencing with Section 55000) of the Health and Safety Code,
application of structural standards necessary to provide for life
safety above current code requirements, and other incentives to
repair the buildings which are available from federal, state, and local
programs. Compliance with an adopted hazardous buildings
ordinance or mitigation program shall be the responsibility of
building owners.
Nothing in this chapter makes any state building subject to a local
building mitigation program or makes the state or any local
government responsible for paying the cost of strengthening a
privately owned structure, reducing the occupancy, demolishing a
structure, preparing engineering or architectural analysis,
investigation or design, or other costs associated with compliance
of locally adopted mitigation programs.
(c) By January 1, 1990, all information regarding potentially
hazardous buildings and all hazardous building mitigation
programs shall be reported to the appropriate legislative body of a
city or county and filed with the Seismic Safety Commission.
8878. Local jurisdictions undertaking inventories and providing
structural evaluations of potentially hazardous buildings pursuant
to this chapter shall have the same immunity from liability foraction
or inaction taken pursuant to this chapter as is provided by Section
19167 of the Health and Safety Code for action or failure to take any
action pursuant to Article 4 (commencing with Section 19160) of
Chapter 2 of Part 3 of Division 13 of the Health and Safety Code.
8879. The Seismic Safety Commission shall report annually,
commencing on or before June 30, 1987 to the Legislature on the
filing of mitigation programs from local jurisdictions. The annual
report required by this section shall review and assess the
effectiveness of building reconstruction standards adopted by cities
and counties pursuant to this article and shall supersede the
Exhibit B (continued)
The URM Law
Ch. 250 -4-
reporting requirement pursuant to Section 19169 of the Health and
Safety Code.
8879.5. The Seismic Safety Commission shall coordinate the
earthquake- related responsibilities of government agencies
imposed by this chapter to ensure compliance with the purposes of
this chapter.
SEC. 3. The sum of one hundred fifty thousand dollars
(S 150,000) is hereby appropriated from the General Fund to the
Seismic Safety Commission to develop the advisory report required
pursuant to Chapter 12.2 (commencing with Section 8875) of
Division 1 of Title 2 of the Government Code.
It is the intent of the Legislature that funding for the program in
the 1987 -88 fiscal year and thereafter be provided for through the
annual budget process.
Costs incurred by local building departments in identifying
potentially hazardous buildings or in preparing a mitigation
program prior to the effective date of this act-shall not be considered
state- mandated costs and shall not be reimbursed pursuant to this
act.
SEC. 4. No reimbursement is required by this act pursuant to
Section 6 of Article XII1 B of the California Constitution because
the local agency or school district has the authority to levy service
charges, fees, or assessments sufficient to pay for the program or
level of service mandated by this act.
Chapter 9 Reference Material 0
Exhibit I
Report to Seismic Safety Commission
Date of Report AUGUST 2, 1989
City MOORPARK County VENTURA
Contact Person: Name CLAUDE STEWART
Street Address 1 1 1 A PQTNr)P.XTP.R AVE.
City MOORPARK Zip 93021
Telephone( 805 ) 529 -3940
• Identifying Buildings
• Number of Buildings Identified as "Potentially Hazardous Buildings"
Type of Bldg. by
Use (primary use)
No. of Bldgs.
Total Sq. Ft.
Retail
Office
Residential
School: Pre - school
School: K -12
School: College
Hotel
Restaurant
Theater
1
Industrial
Warehouse
Garage
1
Public Utility
Hospital
Police Department
Fire Department
Jail
Church
Other
Total
Type of Bldgs. by
Structural System
No. of Bldgs.
Total Sq. Ft.
Bearing Wall
Steel Frame
Concrete Frame
Other
Total
EXHIBIT 20_
• Number of other buildings considered to be historic buildings: Approx. total sq.ft:
• Is field survey complete? ® Yes Q No
If not, estimated date of completion:
Is office verification complete? ® Yes O No
If not, estimated date of completion:
Chapter 9 Reference Material
i
Section 1 (Continued)
'California Seismic Safety Commission Model Ordinance
1 2]
EXHIBITS
MODEL ORDINANCE
CHAPTER 88 ( 1)
EARTHQUAKE HAZARD REDUCTION IN
EXISTING BUILDINGS
NOTE: Code reference - 1985 Uniform Building Code.
X.c�Jr.civ 1
SEC. 8801. 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 unreinforeed masonry bearing
wall buildings constructed prior to [the adoption date of
the Building Code requiring earthquake resistant design of
buildings). such buildings have been widely recognized for
sustaining life- hazardous damage, including partial or complete
collapse during moderate to strong earthquakes.
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 of'life
or injury or prevent earthquake damage to rehabilitated
buildings. This chapter does not require alteration of existing
electrical, plumbing, mechanical or fire safety systems 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 finds deficiencies, this chapter
requires the building to be strengthened or demolished.
Qualified Historical Buildings shall comply with the State
Historical Building Code (SHBC) established under Part 8, Title
24 of the California Administrative Code.
(1) Note: The chapter and section numbering of this model
ordinance -- Chapter 88 and section numbers in the 8800 series- -
follow the numbering of the Los Angeles Ordinance as amended in
early 1985, All chapter number references other than Chapter 88
(e.g., Chapter 23) designate passages in the Uniform Building
Code, 1985 edition.
Section 1(Continued)
California Seismic Safety Commission Model Ordinance
SEC. 8802. SCOPE
The provisions of this chapter shall apply to all buildings
constructed or under construction prior to (adoption date
of local earthquake resistant code requirementsl, or for which a
building permit was issued prior to , which on the
effective date of this ordinance have unreinforced masonry
bearing walls as defined herein.
EXCEPTION: This division shall not apply to detached one or
two family dwellings and detached apartment houses
containing less than 5 dwelling units and used solely for
residential purposes.
SEC. 8803. DEFINITIONS
For purposes of this chapter, the applicable definitions in
Sections 2302 and 2312 of the ' Jniform 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; municipal government disaster
operation and communication centers.
HIGH RISK BUILDING: Any building, not classified an
essential building, having an occupant load of 100 or more, as
determined by Section 3302(a).
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.
LOW RISK BUILDING: Any building, not classified as an
essential building, having an occupant load of less than 20
occupants as determined by Section 3302(a).
MEDIUM RISK .WILDING: Any building, not classified as a high
risk building or an essential building, having an occupant load
of 20 occupants or more as determined by Section 3302(a).
(1) All section - number references in the model ordinance that are
not in the 88 series, e.g., sec. 2303, sec. 2312,.sec. 3302(a), and
so forth, indicate passages in the Uniform Building Code,
1985 edition.
Appendix Section 1
8so n 1(Continued)
California Seismic Safety Commission Model Ordinance
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 2407(h).
SEC. 8804. RATING CLASSIFICATIONS
The rating classifications shown in Table No. 88 -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 Section 3302(a) shall be used to
determine the rating classification.
EXCEPTION: For the purpose of this chapter, portions of
buildings constructed to act independently when resisting
seismic forces may be placed in separate rating
classifications.
SEC. 8805. 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 to 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 within the stated time limits:
(a) Within 270 days after the service of the order, a
structural analysis, which is subject to approval by the
building official, and which shall demonstrate that the building
meets the minimum requirements of this Chapter; or
(b) Within 270 days after the service of the order, the
structural analysis and plans for the proposed structural
alterations of the building necessary to comply with the minimum
requirements of this chapter; or
(c) Within 120 days after service of the order, plans for
the installation of wall anchors in accordance with the
requirements specified in Section 8807(c); or
(d) Within 270 days after the service of the order, plans
for the demolition of the building.
Section 1 (Continued)
California Seismic Safety Commission Model Ordinance
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. 88 -B. These time limits shall
begin to run from the date the order is served in accordance
with Section 8806(a) and (b).
Owners electing to comply with Subsection (c) of this section
are also required to comply with Subsections (b) or (d) of this
section 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 construction for complete structural alterations or
building demolition set forth in Table No. 88 -B shall be
extended in accordance with Table No. 88 -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 8806(b). The time limit for commencing
construction shall commence from the date the building permit is
issued.
SEC. 8806. ADMINISTRATION
(a) Service of Order. The building official shall issue an
order, as provided in Section 8806(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. 88 -C. The minimum time period for the service of such
orders shall be measured from the effective date of Chapter 88.
Upon receipt of a written request from the owner, the building
official shall order a building to'comply 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 as shown on the last equalized assessment,
and upon the person, if any, in apparent charge or control of
the building. The order shall specify that the building has
been determined by the 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 Section 8805 which sets forth the owner's
alternatives and time limits for compliance.
(c) Appeal Form Order. The owner or person in charge or
control of the building may appeal tofthe Board of Appeals)the
building official's initial determination that the building is
within the scope of this chapter. Such appeal shall be filed
with the board within 60 days from the service date of the order
described in Section 8806(b). Any such appeal shall be decided
by the board no 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.
Appendix Section 1
Section. 1 (Continued)
California Seismic Safety Commission Model Ordinance
Each appeal shall be accompanied by a filing fee as set forth in
the code.
Appeals or requests for slight modifications from any other
determinations, orders or actions by the building official
pursuant to this chapter, shall be made in accordance with the
normal appeal procedures established in this 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 88 - Earthquake Hazard Reduction
in Existing Buildings. 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 it is
not found to comply with Chapter 88.
If the building is found not to be within the scope of this
chapter, or as a result of structural 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
certificate terminating the status of the subject building as
being classified within the scope of Chapter 88 - Earthquake
Hazard Reduction in Existing Buildings.
(e) 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 8805, the building
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
additional time as may have been granted by[the appeals board],
the building cfficial may order demolition of the building in
accordance with the Abatement of Dangerous Buildings provisions
of this code.
SEC. 8807. ANALYSIS AND DESIGN
(a) General. Every structure within the scope of this
Division shall be analyzed and constructed to resist minimum
total lateral seismic forces assumed to act nonconcurrently in
the direction of each of the main axes of the structure in
accordance with the following equation:
V =ZIKCSW (88 -1)
The value of IKCS need not exceed the values set forth in
Table No. 88 -1, based on the applicable rating classification of
the building.
Section 1 (Continued)
California Seismic Safety Commission Model Ordinance
(b) Lateral Forces on Elements of Structures. Parts or
portions of structures shall be analyzed and designed for
lateral loads in accordance with Subsections 8807(a) and 2312(e)
of the Uniform Building Code but not less than the value from
the following equation:
Fp= ZICp SWp (88 -2)
For the provisions of this subsection, the product of IS need
not exceed the values as set forth in Table No. 88 -E.
EXCEPTION: Unreinforced masonry walls in buildings not
having a rating classification of I may be analyzed in
accordance with Section 8808.
The value of Cp need not exceed the values set forth in Table
88 -F.
(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 Table No. 88 -F of this code and the equation
Fp= ZICpSWp as modified by Table No. 88 -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 Uniform Building
Code unless otherwise 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
Chapter 23.
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 horizontal forces.
3. Positive Connections. All parts, portions or elements
of the structuze 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 Uniform Building Code and
those materials and types of construction specified in Section
8808.
2. Connections. Materials and connectors used for
interconnection of parts and portions of the structure shall
conform to the Uniform Building Code. Nails may be used as part
of an approved connector.
Appendix Section 1
Section I (Continued)
California Seismic Safety Commission Model Ordinance
3. Unreinforced Masonry Walls. Except as modified herein,
unreinforced masonry walls shall be analyzed as specified in
Section 2406, 2407 and 2408 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. The 50 percent
increase in the seismic force factor for shear walls as
specified in Section 2407(h)4F of the Uniform 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: 1. Unreinforced masonry walls in buildings not
classified as a Rating Classification I pursuant to Table
No. 88 -A may be analyzed in accordance with Section 8808.
2. An unreinforced masonry wall which carries no design
loads other than its own weight may be considered as veneer
if it is 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 2303(f).
2. Existing Materials. When stresses in existing lateral
force resisting elements are due to a combination of dead loads
plus live loads plus seismic loads, the allowable working stress
specified in the Uniform Building Code may be increased 100
percent. However, no increase will be permitted in the stresses
allowed in Section 8808, 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
required by this chapter, the maximum tensile fiber stress may
be reduced by the full direct stress due to vertical dead loads.
SEC. 8808. MATERIALS OF CONSTRUCTION
(a) General. All materials permitted by the Uniform 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. 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 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
Section 1 (Continued)
California Seismic Safety Commission Model Ordinance
extending not less than 4 inches into the backing. The distance
between adjacent full - length headers shall not exceed 24 inches
vertically or horizontally. Where the backing consists of two
or more wythes the header shall extend not less than 4 inches
into the most distant wythe, or the backing wythes shall be
bonded together with separate headers whose area and spacing
conform to the foregoing.
Tension stresses due to seismic forces normal to the wall
may be neglected if the walls do not exceed the height to
thickness ratio in Table No. 88 -G and the in -plane shear
stresses due to seismic loads as set forth in Table No. 88 -J.
If the wall height- thickness ratio exceeds the specified
limits, the wall may be supported by vertical bracing members
designed in accordance with Section 8807. 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 8807(b)
if the deflection at design loads is not less than one -
quarter nor more than one -third of the wall thickness.
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.
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.
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. 88 -H.
(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 88 -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.
Appendix Section 1 e
Section I (Continued)
California Seismic Safety Commission Model Ordinance
(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. Alternate
methods of testing may be approved by the building official.
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 that 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 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 two per wall or line of wall elements resisting a
common force, or 1 per 1500 square feet of wall 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
P10
I
Section 1 (Continued)
California Seismic Safety Commission Model Ordinance
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 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 Special 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 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 8808(e) 3 and 4.
Design stresses shall be related to test results obtained in
accordance with Table No. 88 -J. 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 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 40 percent of the average of
those tested anchors having the same wall thickenss and joist
orientation.
(i) Qualification tests for devices used for wall anchorage
shall be teste3 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
AmarYfix Sarfinn 1
Section 1(Continued)
California Seismic Safety Commission Model Ordinance
resistance value assigned the device shall be 20 percent of the
average of the ultimate loads.
SEC. 8809. 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. All unreinforced masonry walls shall be anchored at the
roof level by tension bolts through the wall as specified in
Table 88 -I, or by approved equivalent at a maximum anchor
spacing 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 force's. 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 8808(h).
When access to the exterior face of the masonry wall is
prevented by proximity of an existing building, wall anchors
conforming to Items 5 and 6 in Table 88 -I may be used.
Alternative devices to be used in lieu of tension bolts for
masonry wall anchorage shall be tested as specified in Section
8808(1).
2. Diaphragm chord stresses of horizontal diaphragms shall
be developed 'n existing materials or by addition of new
materials.
3. Where trusses and beams other than rafters or joists 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 special inspector certified to
inspect masonry or concrete. At the conclusion of the project,
12
Section 1 (Continued)
California Seismic Safety Commission Model Ordinance
the inspector shall submit a written report to the building
official setting forth the portion of work inspected.
6. Repair details shall be prepared for 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. The extent and type of parapet corrections, if any,
which were performed in accordance with the Uniform Building
Code.
4. Accurately dimensioned floor plans and masonry wall
elevations showing dimensioned openings, piers, wall thickness
and heights.
5. The location of cracks or damaged portions of
unreinforced masonry walls requiring repairs.
6. The type of interior wall surfaces and whether
reinstalling or anchoring of ceiling plaster is necessary.
7. The general condition of the mortar joints and whether
the joints neei pointing.
Appendix Section t
Section 1 (Continued)
California Seismic Safety Commission Model Ordinance
TABLE NO. 88 -A
RATING CLASSIFICATIONS
TYPE OF BUILDING
Essential Building
High Risk Building
Medium Risk Building
Low Risk Building
CLASSIFICATION
I
II
III
IV
TABLE NO. 88 -B
TIME LIMITS FOR COMPLIANCE (1)
REQUIRED ACTION OBTAIN BUILDING COMMENCE COMPLETE
BY OWNER PERMIT CONSTRUCTION CONSTRUCTION
WITHIN WITHIN WITHIN
Complete Structural
Alterations or 1 year
Building Demolition
Wall Anchor
Installation
180 days
180 days (2) 3 years
270 days 1 year
(1) Where two or more buildings under separate ownership are to be
rehabilitated simultaneously, an extension can be based on the average
time requirements for the buildings involved, with a suggested minimum
extension of 6 months. An extension could be granted on submission of a
binding agreement between the owners involved, with the actual date of
compliance to be determined by the building official.
(2) Measured from date of building permit issuance. All the other time
limits are measured from the date of the order.
;I �I
Section 1 (Continued)
California Seismic Safety Commission Model Ordinance
Appendx Section t
TABLE
NO. 88 -C
SERVICE PRIORITIES AND
EXTENDED TIME PROVISIONS
Extension of Time
Minimum Time
Rating
Occupant
if Wall Anchors
Periods for
Classification
Load
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
51 to and
including
6 years
2 years
99
20 to and
including
6 years
3 years
50
IV
Less than 20
7 years
4 years
(Lowest Priority)
TABLE
NO. 88 -D
HORIZONTAL FORCE FACTORS BASED
ON RATING CLASSIFICATION
RATING
CLASSIFICATION
IKCS
I
0.186
II
0.133
I:[I
& IV
0.100
Appendx Section t
Section 1 (Continued)
California Seismic Safety Commission Model Ordinance
TABLE NO. 88 -E
HORIZONTAL FORCE FACTORS "IS"
FOR PARTS OR PORTIONS OF STRUCTURES
RATING
CLASSIFICATION IS
I 1.50
II 1.00
III & IV 0.75
TABLE NO. 88 -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 Cp
Exterior bearing and non - bearing walls,
interior bearing walls and partitions,
interior non - bearing walls and
partitions over ten feet in height,
Normal to
masonry fences over six feet in height.
Flat Suface
0.20
Cantilever parapet and other cantilever
Normal to
walls, except retaining walls.
Flat Surface
1.00
Exterior and intericr ornamentations
Any
and appendages.
Direction
1.00
When connected to or a part of a
building; towers, tanks, towers and
tanks plus contents, racks over 8 feet
3 inches in height plus contents,
Any
chimneys, smokestacks, and penthouses.
Direction
0.20(2)(4)
When connected to or a part of a
building: Rigid and rigidly mounted
equipment and machinery not required
Any
for continued operation of essential
Horizontal
occupancies.(5)
Direction
0.20(3)
Tanks plus effective contents resting
Any
on the ground.
Direction
0.12
Section 1 (Continued)
California Seismic Safety Commission Model Ordinance
Floors and roofs acting as
diaphragms.
In the plane of
the diaphragm 0.12(6)
Prefabricated structural elements, Any
other than walls, with force applied Horizontal
at center of gravity of assembly. Direction 0.30
Connections for exterior panels or Any
elements. Direction 2.00
(1) See Section 8807(b) for use of Cp.
(2) When located in the upper portion of any building with a ha /D
ratio of 5 to 1 or greater the value shall be increased by 508.
(3) For flexible and flexibly mounted equipment and machinery, the
appropriate values for Cp shall be determined with consideration
given to both the dynamic properties of the equipment and
machinery and to the building or structure in which it is
placed.
(4) The Wp for storage racks shall be the weight of the racks plus
contents. The value of Cp for racks over two storage support
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(k).
(6) Floor and roofs acting as diaphragms shall be designed for a
minimum force resulting from a Cp of .12 applied to Wp unless a
greater force results from the distribution of lateral forces in
accordance with Section 2312(e).
Appendix Section 1 N
Section.t (Continued)
California Seismic Safety Commission Model Ordinance
TABLE NO. 88 -G
ALLOWABLE VALUE OF HEIGHT - THICKNESS RATIO
OF UNREINFORCED MASONRY WALLS WITH MINIMUM
QUALITY MORTAR. (1) (2)
BUILDING WITH CROSSWALLS AS ALL OTHER
DEFINED BY SECTION 8803 BUILDINGS
Walls of
One Story Buildings 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
(1) Minimum quality mortar shall be determined by laboratory testing
in accordance with Section 8808(e).
(2) Table 88 -G is not applicable to buildings of rating
classification I. Halls of buildings within rating
classification I shall be analyzed in accordance with Section
8807(f).
TABLE NO. 88 -H
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.
b. Roofs with diagonal
sheathing and roofing
applied directly to the
sheathing.
c. Floors with straight
tongue and groove sheathing.
ALLOWABLE VALUES
100 lbs. per foot for
seismic shear.
400 lbs. per foot for
seismic shear
150 lbs per foot for
seismic shear.'
I
Section 1 (Continued)
.California Seismic Safety Commission Model Ordinance
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)
2. SHEAR WALLS
Wood stud walls with
lath and plaster.
3. PLAIN CONCRETE FOOTINGS.
4. DOUGLAS FIR WOOD
5. REINFORCING STEEL
6. STRUCTURAL STEEL
300 lbs. per foot for
seismic shear.
450 lbs. per foot for
seismic shear.
Add 50 lbs. per foot
to the allowable values
for Items la and lc.
100 lbs. per foot each
side for seismic shear.
f' -1500 psi unless
c
otherwise shown by tests.
Allowable stress same as
No. 1 D.F. (3)
f = 18,000 lbs. per
t
square inch maximum. (3)
f - 20,000 lbs. per
t
square inch maximum. (3)
(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 Department.
(3) Stresses given may be increased for combinations of loads as
specified in Section 8807(g)2.
Appendix Section 1
Section 1 (Continued)
California Seismic Safety Commission Model Ordinance
TABLE NO. 88 -I
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.
SHEAR BOLTS
3. 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 bclt or dowel. (1)
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.
75 per cent of the values
specified in Table No. 47 -I.
33 1/3 per cent of the
values specified in
Table No. 47 -I.
100 percent of the values
for solid masonry specified
in Table No. 24E. No values
larger than those given
for 3/4 inch bolts shall
be used.
* All tables that do not carry a 88 number are found in the Unifor:.1
Building Code, 1985 edition.
Section 1 (Continued)
California Seismic Safety Commission Model Ordinance
TENSION BOLTS
4. 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)
WALL ANCHORS (8809(b)l.)
5. Bolts extending to the exterior 600 lbs. per bolt.
face of the wall with a 2 1/2
inch round plate under the head.
Installed as specified for shear
bolts. Spaced not closer than
12 inches on centers. (1) (2)
6. Bolts or dowels extending to the 1200 lbs, per bolt
exterior face of the wall with or dowel.
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)
INFILLED WALLS
7. 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.
REINFORCED MASONRY
8. Masonry piers and walls Same values as specified
reinforced per Section 2407. in Division 26, UBC.
REINFORCED CONCRETE
9. Concrete footings, walls and Same values as specified
piers reinforced as specified in Division 26, UBC.
in Division 26 and designed
for tributary loads.
A --f- C-C- 4
Section 1(Continued)
California Seismic Safety Commission Model Ordinance
EXISTING FOUNDATION LOADS
10. 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
258 for dead load, and may
be increased 508 for dead
load plus seismic load
required by this Division.
(1) Bolts and dowels to be tested as specified in Section 8808(f).
(2) Bolts and dowels to be 1/2 inch minimum in diameter.
TABLE NO. 88 -J
ALLOWABLE SHEAR STRESS FOR TESTED
UNREINFORCED MASONRY WALLS
Eighty percent
of test results
in psi not less
than
30 plus axial stress
40 plus axial stress
50 plus axial stress
100 plus axial stress
or more
Average test results
of cores in psi
20
27
33
67 or more
Seismic in -plane
shear based on
gross area (1)
3 psi
4 psi
5 psi
10 psi max
(1) Allowable shear stress may be increased by addition of 108 of the
axial stress due to the weight of the wall directly above.
22
Section 1 (Continued)
Cplifornia Seismic Safety Commission Model Ordinance
GLOSSARY OF SYMBOLS AND NOTATIONS
C
= Numerical coefficient
as specified
in Section 2312(d)
Cp
= Numerical coefficient
as specified
in Section 2312(g) and
as set forth in Table
No. 23 -1
D
= The dimension of the
structure, in
feet, in a direction
parallel to the applied
forces
fc =
Specified compressive
strength of
concrete, psi
Fp = Lateral forces on a part of the structure and in the direction
under consideration
ft = Allowable tensile stress, psi
h = Height in feet above the base to level n
I = Occupancy Importance Factor as set forth in Table No. 23 -K
S = Numerical coefficient for site - structure resonance
V = The total lateral force or shear at the base
W = The total dead load as defined in Section 2302 including
the partition loading specified in Section 2304(d) where
applicable
Wp = The weight of a portion of a structure or nonstructural
component
Z = 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
= 3/4. For locations in Zone No. 4, Z = 1
Appendix Section 1