HomeMy WebLinkAboutOrd 1972-1410 � 3
ORDINANCE N0. 1410 .
AN ORDINANCE Of THE CITY OF CHULA VISTA, CALIfORNIA AMENDIPJG SECTION 8. 14
OF CHAPTER 8 OF THE CHULA 4ISTA CITY CODE RELATING TO CHAPTER 23 AND
CHAPTER 26 OF THE UNIFORM BUILDING CODE 1970 EDITION AS ADOPTED BY SECTION
8. 1 OF THE CHULA VISTA CITY CODE.
THE CITY COUNCIL OF THE CITY OF CHULA VISTA, CALIFORNIA DOES ORDAIN AS FOLLOWS :
SECTION I . That Section 8. 14 of Chapter 8 of the Chula Vista City Code be, and the
same time are, hereby amended to read as follows :
1 . Section 2314(c) of the Uniform Building Code is hereby revised by deleting
therefrom the following symbols and notations.
J = Numerical coefficient for base moment as specified in Section 2314(h).
JX = Numerical coefficient for over turning moment at level "x".
2. Section 2314(h) of the Uniform Building Code is hereby revised to read as
follows :
(h) Overturning. Every building or structure -shall be designed to resist the
overturning effects caused by the wind forces and related requirements specified
in Section 2308, or the earthquake forces specified in this Section, whichever
governs.
The overturning mqnent due to earthquake forces, "MX" , at any level designated
as x shall be determined in accordance with the following:
n
Mx = Ft �hn - hX) +XF� �h� - hX) - - - - - �14 - 7)
At any level the incremental changes of the design overturning moment, in the
story under consideration, shall be distributed to the various resisting elements
in the same proportion as the distribution of the shears in the resisting system.
Where other vertical members are provided which are capable of partially re-
sisting the overturning moments , a redistribution may be made to these members
if framing members of sufficient strength and stiffness to transmit the required
loads are provided.
Where a vertical resisting element is discontinuous , the overturning moment
carried by the lowest story of that element shall be carried down as loads to
the foundation.
3. Section 2314(j)1 of the Uniform Building Code is hereby revised to read as follows:
(j) Structural Systems. l . Design requirements.
A. All buildings desi9ned with a horizontal force factor "K" = 0.67 or 0.80
shall have space frames - ductile manent resisting.
B. Buildings more than one hundred and sixty feet (160' ) in height shall have
space frames - ductile moment resisting capable of resistin9 not less than �
25% of the required seismic forces for the structure as a whole.
EXCEPTION : Buildings more than 160 feet in height in Seismic Zone No. 1
may have concrete shear walls designed in conformance with Section 2632
of this Code in lieu of a ductile moment - resisting space frame, provided
a "K" value of 1 .00 or 1 .33 is utilized in the design.
C. All concrete space frames required by design to be part of the lateral force
resisting system shall be space frames - ductile moment resisting.
D. All framing elements not required by design to be part of the lateral force
resisting system shall be .investigated for adequacy for vertical load carrying-
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capacity at four (4) times the distortions resulting from the code required
' lateral forces. The rigidity of other elements shall be considered in
accordance with Section 2314(e) .
E. Moment - resisting space frames and ductile moment-resisting space frames
may be enclosed by or adjoined by more rigid elements which would tend to
prevent.the space frame from resisting lateral forces where it can be shown
that the action or failure of the more rigid elements will not impair the
vertical and lateral load resisting ability of the space frame.
f. Other structural concepts may be approved by the Building Official when
evidence is submitted showing that equivalent ductility and energy absorption
are provided.
4. Section 2608(a) of the Uniform Building Code is revised by adding a subsection
four (4) to read as follows.
4. For tie anchorage in Seismic Zone No. 3 (See Figures No' s 1 , 2, and 3, Pages
122 and 123) a minimum turn of 135 degrees plus an extension of at least six
bar dismeters but not less than 4 inches at the free end of the bar.
5. Section 2608(f) of the Uniform Building Code is hereby revised by adding a new
paragraph between the third and.fourth paragraphs to read as follows.
All longitudinal bars for tied columns in Seismic Zone No. 3 (See Figure l , 2,
and 3, pages 122 and 123) shall be .enclosed by laferal ties. The ties shall be
so arranged that every corner and alternate longitudinal bar shall have lateral
support provided by the corner-of a complete tie having an included an91e of not
more than 135 degrees or by a hook at the end of a tie and no bar shall be
farther than six inches (6") from such laterally supported bar. Where the bars
are located around the periphery of a circle , a complete circular tie may be used.
EXCEPTION: In regions of columns confined by special transverse
reinforcement conforming to the provisions of Section 2630,
supplementary crossties engaging the hoops only may be considered
as meeting this requirement:.
Ties shall be at least three-eighth of an inch (3/8") in diameter except that
ties providing lateral support for �11 or larger longitudinal bars and bundled
longitudinal bars, shall be at least one-half (;") inch in diameter. Ties shall
be spaced apart not over 8 bar diameters, 24 tie diameters or one-half of the
dimension of the column in the top and bottom portions of the column over a
length equal to the maximum column dimension or one-sixth of the clear height
of the column, but not less than 18 inches. In other portions of the column,
the ties shall be located not .farther from the ends of the column than one-half
a tie spacin9.
6. Section 2612(j) of the Uniform Buildin9 Code' is hereby revised to .read as follows.
(j) Shear Walls. Shear stresses in shear walls shall be limited in accordance
with the following.
1 . The nominal shear stress resulting from forces acting parallel to shear walls
shall be computed by:
v = A (12 - 12)
c
Where: V = shear computed according to Section 2314(e) and including the .
effect of gravity loads
A� = area of concrete section resisting V , sq. in.
2. In walls �ahere the critical design shears are from forces other than seismic
forces the shear stress "v" shall not exceed either of the followin9:
��
�
3
v = 1 .0 f� + 1 .0 pfv (12 - 13)
v = 4.0 � (12 - 14)
EXCEPTIONS: The limit given by formula (12 - 14) shall be modified
as follows:
1 ) the average horizontal shear "v" for all wall piers sharing
a common lateral force component shall not exceed 4.0 �and
the shear "v" in any individual pier may not be more than
5.0 , f�
2) The value of the vertical shear "v" shall not exceed
5.0 1�- for horizontal wall elements.
3. In walls where the critical design shears are from forces including seismic
forces, and the lateral load resisting system has a 100% moment resisting
space frame, the shear stress "v" shall not exceed either of the following:
v = _.9 \� + .9 pfv (12 - 15)
v = 3.6 f� (12 - 16)
EXCEPTIONS: The limit given by fottnula (12 - 16) shall be modified
as follows :
1 ) The avera9e horizontal shear "v" for all wall piers sharing a
cormnon lateral force component shall not exceed 3.6 � and.the
shear "v" in any individual pier may not be more than 4.� �f'�
2) The value of the vertical shear "v" shall not exceed 4.5 �
for horizontal wall elements.
4. In walls where the critical design shears are from forces including seismic
forces, and the lateral load resisting system does not have a 100% moment
resisting space frame , the shear stress "v" shall not exceed either of the
following:
v = .45 � + .45 pfv (12 - 17)
v = 1 .8 f� (12 - 18)
EXCEPTIONS: The limit given by formula (12 -18) shall be modified as
follows :
1 ) The average horizontal -shear "v" for all wall piers sharing a
common lateral force component shall not exceed 1 .8�f� and the
shear "v" in any individual pier may not be more than 2.�5 V f�
2) The value of the vertical shear "v" shall not exceed 2.25 �
for horizontal wall elements.
5. In formulas (12 - 13) , (12 - 17) ",p" is the ratio of the area of the
reinforcement to the area of concrete section resisting the shear "V".
At least an equal percentage of reinforcement "p" shall be rovided
perpendicular to that required to satisfy formulas (12 - 13�, (12 - 15)
and (12 - 17).
6. The allowable stresses given in formulas (12 - 13) through (12 - 18) and
exceptions 1 and 2 may be increased in accordance with the provisions of
Section 2303.
7. When structural li9htweight concretes .are used, the limiting value of the
shear. stress carried by the concrete alone shall be 0. 15 FSP times the
value in formulas (12 - 13) , . (12 - 15) and (12 - 17) .
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7. Section .2617(j) of the Uniform Building Code is hereby revised to reas as
follows :
(j) Shear Walls. Shear stresses in shear walls shall be limited in
accordance with the following:
1 . The .nominal ultimate shear stress.-resulting from forces acting parallel
to shear walls shall be computed by:
v� _ �u (17 - 11 )
Ac
Where: V� = Ultimate shear .computed according to:Section 2314(e)
and including the effect of gravity loads.
A� = Area of concrete section resisting V� , sq. in.
2: The ultimate shear stress v� thus computed shall not exceed that
given by:
vU = 2¢ � f� + �Pfy (17 - 12)
Where "p" is the ratio of the area of reinforcement to the area of concrete
section resisting the shear V� , at least an equal percentage of reinforce-
ment, p, shall be provided perpendicular to that required to satisfy Eq.
(17 - 12) .
3. The average horizontal shear v� for all wall piers sharing a common lateral
force component shall not exceed 8¢ �f'� and the vU in any of the indi-
vidual wall piers shall be not more than lOb f� for horizontal wall
elements.
4. When structural lightweight concretes are used, the. ultimate shear stress
calculated by formula (17 - 12) .shall be modi.fied as follows :
�� = 0.3� FSP � f� + �PfY �17 - 13) .
8. Section 2630 of the Unifottn Building Code .is. hereby-revised .to .reas as follows :
Section 2630 Concrete Ductile Moment-Resisting Space Frames
(a) General . 1 . Design and construction of .cast-in-place> monolithic reinforced
concrete-framing members and- their connections in ductile.moment -resisting space
frames shall conform to the requirements of this Chapter and al.l the requirements
of this Section 2630.
EXCEPTION: Precast concrete fr.ame .members may be used if the
resulting .construction complies with all the provisions of this
section. ..
� 2. All lateral load-resisting frame member-s. shall be designed by the ultimate
strength design method except.that -the working stress design method may be
used provided.that it is shown that.the factor of safety is equivalent to
that acliieved;with the� ultimate strength design method.
3. Formulas (15 - 2) and (15 - 3) of Section 2615(g) for earthquake loading
shall be modified to:
U = 1 .40 (D + L + E) (30 - 1 )
U = .90 D + 1 .40 E (30 - 2)
4, Members of space frames which are designed to resist seismic forces shall be
designed, in accordance with the provisions of this section , so that shear
failures will not occur if the frame is subjected to lateral displacements
' in excess of yield displacements.
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(b) Definitions. 1 . Confined Concrete. Concrete which is confined by closely
spaced special transverse reinforcement which is provided to restrain the
concrete in directions perpendicular-to the applied stresses.
2. Special Transverse Reinforcement. Spirals, stirrup ties, or hoops and
supplementary crossties provided to restrain the concrete to make it
qualify as confined concrete.
3. Stirrup-ties -or Hoops. Continuous reinforcing steel of not less than a
No. 3 bar bent to form a closed hoop which encloses the longitudinal rein-
forcing and the.ends of which have a standard 135 degree bend with a ]0 bar
diameter extension or equivalent.
(c) Symbols and Notations . The following -symbols. and notations apply only to
the provisions of this Section:
A9 = gross area of column.
AS = effective cross-sectional area of reinforcement.
d = distance from extreme compression fiber to centroid of tension
reinforcement.
f� = compressive stren9th of concrete (see Section 2603).
fy = specified yield strength of reinforcement.
Pd = maximum design axial load on column.
p = tension reinforcement ratio.
p' = compression reinforcement ratio.
D = nominal diameter of bar, inches.
�o = difinition given in Section 2618.
U� .= definition given in Section 2618.
V� = total ultimate shear.
(d) Physical Requirements for Concrete and Reinforcing Steel .
l . Concrete. The minimum specified 28-day strength of the concrete, f�, shall
be 3000 pounds per square inch.
The maximum specified strength for lightweight concrete shall be limited to
4000 psi .
2. Reinforcement. All lon9itudinal reinforcing steel in columns and beams shall
comply with Uniform Building Code Standard 26-7 and limited to ASTM A-615,
grade 40 or 60. The actual yield stress , based on mill tests , shall not
exceed the minimum specified yield stress , fY, by more than 18,000 psi .
Retests shall not exceed this value by more than an additional 3000 psi .
In addition ,•=the ultimate tensile stress shall be not less than 1 .33 times
the actual yield stress, based on mill tests. Grades other than these
specified for design shall not be used.
Where reinforcing steel is to be welded, a chemical analysis of the steel shall
be provided. The welding procedure shall be as set forth in Uniform Buildin9
Code Standard No. 26 - 16.
(e). Flexural Members. 1 . General . Flexural members shall not have a width-
depth ratio of less than 0.3, nor shall the width be less than ten inches (10")
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nor more than the supporting column width plus a distance on each side of
the column-of three-fourths the depth of the flexural member: Flexural
members framing. into columns shall be subject to a rational joint analysis.
2. . Reinforcement. All flexural members shall have a minimum reinforcement
ratio, for top and for bottom reinforcement, of .200 throughout.their length.
fy
The reinforcement ratio, p, shall not exceed 0.025.
The positive moment capacity at the face of columns shall be not less than
50 per cent of the negative moment capacity provided. A minimum of one-
fourth of the larger amount-of the negative reinforcement required at either
end shall continue throughout the length of the beam. At least two bars
shall be provided both top and bottom.
3. Splices. Tensile steel shall not be spliced by lappin9 in a region of
tension or reversing stress unless the region is confined by stirrup-ties.
Splices shall not be located within the column or within �a distance of twice
the member depth from the face of the column. At least two stirrup-ties
shall be provided at all splices.
4. Anchorage. Flexural members terminating at a column, in any vertical plane ,
shall have top and bottom reinforcement extending �aithout horizontal offsets ,
to the far face of a confined concrete region (Section 2630(f) 4) , terminating
in a standard 90 degree hook. Len9th of anchorage in confined regions shall
be determined by:
L = ASfy , including hook and vertical extension, (30 - 3) ,
1 .5u� o but not less than 24 inches. .
EXCEPTION: Where the column resists less than 25% of the story-bent
shear, at least 50% of such top and bottom reinforcement shall be .
anchored within such solumn cores and the remainder shall be anchored
in regions outside the column core confined as specified herein for
columns.
5. Web Reinforcement. Vertical web reinforcement of not less than No. 3 bars
shall be provided in accordance with the requirements of Section 2617 ,
except that:
M° + MB (30 - 4)
A. Maximum V� _ u u + � .4Vp + �
L
where MA and MB are ultimate moment capacities of opposite sense at
each en� of the member and Vp +� is the simple span shear.
Ultimate moment capacities shall be computed without the ¢ factor
reduction and assuming the maximum reinforcing yield strength based
on 25% over specified yield. Ultimate shear capacities shall be
computed with the � factor reduction.
B. Stirrups shall be spaced at no more than d/2 throughout the length of
the member.
C. Stirrup-ties , at a maximum spacing of not over d/4, 8 bar diameters ,
24 stirrup tie diameters , or twelve inches (12") , whichever is least,
shall be provided in the following locations :
l . At each end of all flexural members. The first stirrup-tie shall
be located not more than to-�o inches (2") from _the face of the
column and the last, a distance of at least twice the member depth
from the face of the columns.
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2. Wherever ultimate moment capacities may be developed in the-
flexural members under inelastic lateral displacement of the frame.
3. Wherever required compression reinforcement occurs in the flexural
members.
D. In regions where stirrup-ties are required , longitudinal bars shall
have lateral support conforming to the provisions of ties for tied
columns. Single or overlapping stirrup-ties and supplementary crossties
may be used. .
(f) Columns Subject to Direct Stress and Bending. 1 .. Dimensional
Limitations. The ratio .of minimum to maximum column thickness
shall not be less than 0.4 nor shall any dimension be less than
twelve inches (12").
2. Vertical Reinforcement. The reinforcement ratio, p, in tied columns
shall not be less than 0.01 nor greater than 0.06.
3. Splices. Lap splices shall be made within the center half of
column height, and the splice length shall not be less than 30 bar
diameters. .Continuity may also be effected by welding or by
approved mechanical devices provided.not more than alternate bars
welded or mechanicelly spliced at any level and the vertical distance
between these welds or splices of adjacent bars is not less than
twenty-four inches (24").
4. Special Transverse Reinforcement. The cores of columns shall be
c�nf.ined by special. transverse reinforcement as specified herein
or as required to meet shear requirements.
A. The volumetric ratio of spiral reinforcement shall not be less
than that required in Section 2609(1 ) nor p" = 0. 12 f�' (30 -5) ,
fyb
B. The total cross-sectional area (A"Sh) of rectangular hoop rein-
forcement shall not be less than A"Sh = 0.30 ah" f�(Ap - 1 )
(30 - 6) nor fyb
A"Sh = 0. 12 ah" � (30 - 7) whichever is greater, where
fyb
a = center. to center spacing of hoops in inches with a
maximum of four inches (4") .
. A� = area of column core. .
A9 = gross area of column.
A"Sh = total cross-sectional area in square inches of hoop
reinforcement-including supplementar.y crossties having
a spacing of (a) inches and crossing a section having
a core dimension of h".
h" = core dimension of tied column in inches.
fYb = yield strength of hoop or spiral reinforcement.
Single or overlapping hoops may be provided to meet this
requirement.
Supplementary crossties of the same size and spacing as hoops using
135o minimum hooks engaging the periphery hoop and secured to a
longitudinal bar may be used. Supplementary crossties or legs of
� �o
a
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overlapping hoops shall not be.spaced more than 14" on center
transversely.
EXCEPTION : Equation (30 - 6) need not be complied with if
the column design is based on the column core only.
C. Special transverse reinforcement shall be provided in that
portion of the column over a length equal to the maximum column
dimension or one-sixth of the clear height of the column, but
not less than eighteen inches (18") from either face of the
joint.
D. At any section where the ultimate capacity of the column (P�)
is less than the sum of the shears ( V ) computed by Equation
30 - 4 for all the beams framing into tke column above the level
under consideration, special transverse reinforcement shall be
provided. For beams framing into opposite sides of the column ,
the moment components of Equation 30 - 4 may be assumed to be
of opposite sign. For the purpose of this determination, the •
factor of 1 .4 in Equation 30 - 4 may be changed to 1 .1 . For
determination of P� , the moments resulting from Equation 30 - 4
may be assumed to result from deformation of the frame in any
one principal axis.
E. Columns which support discontinuous members, such as shear walls,
braced frames , or other rigid elements shall have special trans-
- verse reinforcement for the full hei9ht of the supporting columns.
5. Column Shear. The transverse reinforcement in columns subjected to
bending and axial compression .shall satisfy the following requirements:
A�fY d = V� - V� - (30 - 8) .
s
WHERE
V�� the maximum ultimate shear, shall be computed by usin9 the yield
moments in the ends of either the beams or columns framing into the
connection. Ultimate moment capacities shall be computed without 0
or other reduction factors and .under.all possible vertical loading
conditions _and assuming the maximum reinforcing yield strength based
on 25% over specified yield. Ultimate shear capacity shall be com-
puted with the b factor reduction and shall be based on the column
core area for shear resistance.
V� = v�bd, where v� shall be in accordance with Section 2617(b) ,
except that v� shall be considered zero when P <0. 12f�.
Ag
S = spacing, < Z minimum column dimension.
d = effective depth of section.
A� = total cross sectional area of special transverse reinforcement
in tension within a distance s, except that two-thirds of such
area shall be used in the case of circular spirals.
(g) Beam-Column Connection. Special transverse reinforcement shall be pro-
. vided through .the beam column connection.
l . Analysis. The transverse reinforcement through the connection shall
be proportioned .according .to the requirements of Section 2630(f)4.
The transverse reinforcement thus selected shall be checked according
to-the provisions .set forth in Section 2630(f)5 with the exception
. that the Vu acting on- the connection shall be equal to the maximum
shears in the connection computed� by a rational analysis taking into
account the column shear and the concentrated shears developed from
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the forces in the beam reinforcement at a stress assumed at fy.
2. Special transverse column, reinforcement of one-half the amount
otherwise required by.5ubsection (g) 1 . shall be required within
the connection, determined by the depth of the shallowest framing
member, where such members• frame into all four sides of a column
and whose width is at least three-fourths the column width. When
a corner of a tied column, unconfined by flexural members , exceeds
four inches (4" ) , the full special transverse reinforcement shall
be provided through the connection and around bars outside of the
connection.
3. Special transverse beam reinforcing shall be provided through the
beam column connection to -provide confinement for longitudinal re-
inforcement outside the column core where such confinement is not
provided by another beam framing into the connection.
4. Design Limitations. At any beam-column connection �ahere P �0. 12f�
A9
the total ultimate moment capacity of the column, at the design
earthquake axial load, shall be greater than the total ultimate
moment capacity of .the beams , along their principal planes at that
connection.
EXCEPTION : Where certain beam-column connections at
any level do not comply with the above limitations,
the remaining columns and connected flexural members
shall comply and further shall be capable of resisting
the entire shear at that level accounting for the
altered relative rigidities and torsion resulting
from the omission of elastic action of the nonconforming
beam column connections.
(h) Inspection. For buildings designed under this Section, a specially
qualified inspector under the supervision of the person responsible for
the structural design shall provide continuous inspection of the placement
of the reinforcement and concrete> and shall submit a certificate in-
dicating compliance with the plans and specifications.
9: Section .2632(a)3 of the Uniform�Building Code is hereby revised to read as follows :
Formulas (15 - 2) and (15 - 3) of Section 2615(g)..for. earthquake loading shall be
modified to:
U = 1 .4(F+L) + 1 .4E (32 - 1 )
U = 0.9D + 1 .4E (32 - 2)
provided further that 2.8E shall ,be.•used in Formula (32 - 1 ) and 2.8E shall be
used in �Formula (32 - 2) in calculating shear and diagonal tension in buildings
without_a 100 percent moment resisting space frame.
.. � . - - -
10. Section 2632 of the Uniform Building Code is hereby revised by adding subparagraph
(d) and shall read as follows:
(d) Reinforcing Details for Shear Walls.
1 . The minimum reinforcing ratio "p" for all walls designed to resist code
seismic forces acting parallel to the wall shall be .0025 each way.
The maximum spacing of reinforcement each way shall not exceed d/3 or
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18 ; whichever is smaller, where "d" is the dimension of the wall element
parallel to the shear force. That portion of the wall reinforcement
required to resist design shears shall be uniform;y distributed.
2. Wall reinforcement required to resist wall shear shall be terminated tiaith
not less than a 90° bend plus a 6 bar. diameter extension beyond the
boundary reinforcing at vertical and horizontal end faces of wall
secions. Wall reinforcement tettninating in boundary columns or beams
shall be fully anchored into the boundary elements.
11 . Table 26-D of the Uniform Building Code is hereby revised to read as follows :
TABLE N0. 26-D--ALLOWABLE STRESSES IN CONCRETE
DESCRIPTION � I For any �
strength ALLOWABLE STRESS IN PSI
of concrete
in accordance fc= � f�_ f� _ � f� = f� _
with Section -
2605(c) 2�00 I 2500 �3000 � f�000 � 5000
� � I
�
Modulus of elasticity 29,000,000 i I I
ratio:n
for concrete weighing w� • 533 � f�
145 lb. per cu. ft. �
(See Sec. 2611 (c) ) n 11 i 10 9 8 7
� ;
Flexure: f� I
Extreme fiber stress in �
compression f� 0.45f� 900 1125 1350 1800. � 2250
Extreme fiber stress i
in tension in I i i
plain concrete !
footings and walls f� 1 .6 f� I 71 � 80 I 88 � 102 I 113
� i
Shear: v (as a measure I i � I
of diagonal tension at a I �
di s tance "d" f rom -the : �_ a �
face of the support)
Beams with no web I �
reinforcementl v� 1 . 1 f� 49 I 55 60 70 � 78
Joists with no web
reinforcement v� 1 .2 f� 54 I 61 66 77 � 86
Members with vertical i
or inclined web I
reinforcement or
properly combined
bent bars and
vertical stirrups v 5 � f� 223 I 250 174 316 354
i
Shear in walls
resisting other than
seismic forces: 2
Shear carried
by concrete 3 v� 1 .0 f� 45 50 55 63 71
Shear carried
by concrete and
reinforcement 4 v 4.0 f� 180 200 220 253 282
�0
J . . . . . .
11
Shear in walls (
resisting seismic �
forces in buildings �
with a 100% moment I
resisting space
frame: 6
Shear carried �
by concrete 3 v� 0.9 f� 40 45 49 57 63
Shear carried by
concrete and
reinforcement 4 v 3.61� f� 160 180 197 228 � 255
�
Shear in walls I
resisting seismic I
forces in buildings
without a 100% �
moment resisting
space frame: 6 i
Shear carried by
concrete 3 v� 0.45 f� 20 22 24 28 32
Shear carried by
concrete and
reinforcement 4 v 1 .8 i f� 80 90 98 114 127
*l , For shear values for li9ht�aeight aggregate concrete see Section 2612(i ).
2 The stresses indicated may be increased one-third when caused by wind forces.
3 For shear values for lightweight aggre9ate concrete, see Section 2612(j)(7) .
4 Allowable shear carried by concrete and reinforcement can be increased by 1 .25 for
individual wall piers and horizontal wall elements. See Sections 2612(j)(2) ,
2612(j) (3) , and 2612(j) (4) .
5 This increase shall be permitted only when the least distance between the edges _of
the loaded and unloaded areas is a minimum of one-fourth of the parallel side
dimension of the loaded area. The allowable bearing stress on a reasonably con-
centric area greater than one-third but less than the full area shall be inter-
polated between the values given.
6 The stresses indicated may be increased one-third when caused by seismic forces.
SECTION II : If any section, subsection, sentence, clause or phrase of this ordinance is
for any reason held to be unconstitutional , such decision shall not affect the validity
of the remaining portions of this ordinance, irrespective of the fact that any one or more
sections, subsections , sentences, caauses or phrases be declared unconstitutional .
SECTION III : A violation of any provision or the failure to comply with any of the re-
quirements of this ordinance constitutes a misdemeanor. Any person convicted of such
violation or.such failure shall be punishable by a fine of not more than five hundred
dollars (5500.00) or by imprisonment in the County jail for a period of not more than
six (6) months or by both such fine and imprisonment.
SECTION IV: This ordinance shall take effect and be in full force on the thirty-first
day from and after its passage and approval .
Presented b Approved as to or by
� - .�'� \ / .�CJ `-�'/i .r �
e ra y, Dire tor of Builriing George �'/. Lindberg , City Attor e�
d Housing Ins ection
I
ADOPTED A,*�D APPROVED, BY THE CITY COUNCIL OF THE CITY O�
CHULA: AISTA, CALIFOPyIA; this $th day of . August . 197 �
. ,
by the following - vote , to-wit: .
AYES : CUUttC-i.Em2rt Scott, Hobel, Hamilton, Egdahl •
NAYES : Counc�Pmen �one -
ABSE�IT : Cou�tc�Cmen Hyde -
� � 2?�/Y/ �'
^ h a�on o� .t e C�..t o b .0 u2a V.ca.ta%
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STATE OF CALIFORNIA ) '
COJNTY OF SAD] DIEGO j ss.
CITY OF CHULA. VISTA- j �
I , JENNIE M. FULASZ , C�,.ty; C.Cehk os .the .C�..ty•� oS :.Chuka V�,ati�,
CaZi,6onn.Ca, DO NEREBY CERTIFY .tha.t .the: abo�e and. bonego�.ng �.6 a .. su22,
.t�cue and- connec# copy o6 ,
and tiha-t .the eamE hao no.t been amended _on nepeaCed.
DATED:
c�,xy c en
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