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IHEIGHT LIMIT523&4
(feet)
IBASIC
STRUCTURALSYSTEM2 LA TERAL-FORCE-RESISTING SYSTEM R .0.0
1 Bearing wall system
5.54.5
2.62.6
ffiffi
4.54.52.8
2.82.82.2
16)16)EX)
I 2.2
2.2
2.22.8
100
e;
4.42.82.8
I 7.02. Building frame system 240
6.55.0
2.82.8
EX)
EX)
5.55.5
2.82.8
24016)
5.65.65.6
2.22.22.2
100
ffi
6.4 2.2
2.82.82.82.8
2403. Moment-resisting frame
system 8.58.56.55.5
NoLo
NoLo
100
,,~,rl",,:{f I 2.8
2.82.8
2.82.82.8
i 2.8I 28I!
28
28
100I
2~
4 Dual system
8.54.26.55.5424.26.0
N.L.100100100100
100
282.8
2.82.82.82.8
8.54.2
N.L100
6.54.26.54.2
N.L.100
7.54.22.2
2.8I 2.8I 2.0
NoL.100~7
1. Ught-framed walls with shear panelsa. Wood structural panel walls for structures three stories or lessb. All other light-framed walls
2. Shear wallsa. Concreteb. Masonry
3. Ught steel-framed bearing walls with tension-{)nly bracing4. Braced frames where bracing carries gravity load
a. Steelb. ConcreteJc. Hea timber
1. Steel eccentrically braced frame (EBF)2. Ught-framed walls with shear panels
a. Wood structural panel walls for structures three stories or lessb. All other light-framed walls
3. Shear wallsa. Concrete jb. Masonry
4. Ordinary braced framesa. Steelb. ConcreteJc. Heavy timber ,
5. Special concentrically braced frames ""~:;.a. Steel
1. Special moment-resisting frame (SMRF)a. Steelb. Concrete~
2. Masonry moment-resisting wall frame (MMRWF)3. Concrete intermediate moment-resisting frame (IMRF)s4. Ordinary moment-resisting frame (OMRF)
a. Steel"b. ConcreteS
i ~. ~!:::~al.~~~ moment frames of steel (STMF)i 1. Shear walls
a. Concrete with SMRFb. Concrete with steel OMRFc. Concrete with concrete IMRFSd. Masonry with SMRF'
I e. Masonry with steel OMRFf. Masonry with concrete IMRFJ
I g. Masonry with masonry MMRWF2. Steel EBF
a. With steel SMRFb. With steel OMRF
3. Ordinary braced framesa. Steel with steel SMRFb. Steel with steel OMRFc. Concrete with concrete SMRFJd. Concrete with concrete IMRFJ
4. Special concentrically braced framesa. Steel with steel SMRFb. Steel with steel OMRF
1. Cantilevered column elements5. Cantilevered column
6. Shearwail-frame 5.5 2.8 16)1. Concrete"
Undefined system See Sections 1~.6.7 and 1629.9.2 -
25
i,
.;.,U~2,~~~:~~~.Ji,~~~~~,=
FOOTNOTES FOR TABLE 16-N
N.L.-no limit
See Section 1630.4 for combination of structural systems.
2 Basic structural systems are defined in Section 1629.6
3 Prohibited in Seismic Zones 3 and 4
4
Section1634.2.
1
requirements of Section 2211.6 may use a R value of 8.
7
8 Prohibited in Seismic Zones 2A, 28, 3 and 4. See Sec;tion 1633.2.7.
26
J1""
-
I'
,.
j
'I
\ ~I\ I\ I
\\
Elements,
\\ .1\ 1
\ I\.1\ ' I
\ I
\;-~\. j
Late ral \ 1F \ Iorces \ 1
\-.;.-.,.!.I
Shearwalls or
Braced Frames\ I\-..;\ II I
\0lio-]I II I\~III I\1
l"""""""""""""""""".-""",""""""""""""""""""""",""""""""""""""""""""",
Sec 1629.6.3
jl;tJ~
l"oaiJ;~i"" ..--,;"" -
-
Gravity Loads---l--- r r ---r--t_-j--_t ---+- -_t
\~!
~--~\ r\ I
~>~:,;~
~~b~~-~..~~
~~~"~~~~~.."t~i~
t
~~I,;;~~~~~~Jj-to
" ~I
\ I\ II I~Lateral
Forces i l\ I\ I\~\~ I\ I\ I
\--i\ I\ I
===J [~=~===
~=~~=:J [~~~==
~~=~=: ] [~===
~~:=~=~J [~=:~=:=
~:=~~~~~~ ] [~~~==
~~::=~~:~ ] [~~~==
~=~~~~~J [==:=~=:=:J [=~=~=
~\ J ~==~J [==~=~\ I ~~==~==) I\ I I\1 """"""""""""""""" """"""""""
"""""""""""""""""""""""""""~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Sec 1629.6.4
provides resistance for lateral forces
29
~
-
Gravity Loads
l---£--l--- ,__j___i., t_-~
\ "'1
\\~1\ r\ t
\--~
~iLateralForces \~
Sec 1629.6.5
for gravity loads. Moment frame and shear walls
(or braced frames) provide resistance to lateral forces"
Moment frame alone must be able to resist 25 percent
30
-
Sec 1629.6.6
.Cantilevered-columns resist lateral forces. ..fixed at base
with zero moment restraint at top
base member
2.2-
31
-
ii;ilit
~
~
p;=--
I
Lateral ~IForces \\ i
\-""!
SWR = 4.5
6.
.Combination of shearwalls and moment frames to resist
.Prohibited in Seismic Zones 2,3 & 4. ..intended for zones
of low-seismicity. ..Seismic Zones 0 & 1
= 5.5
32
~r~i:~~:;,~~~~~~~~~~r~~,~f~~~~.,~,,-"""'~~;.~
E~~£.-~~E~~
~f~~E:EEE.~f2, f
"rt,
--
"/,, /"/,,/,, /fXIXIXlXIXIXIXlXI'\/,,/ ,,/~/~/
\/'-
/'-/\ A /rXIX!X!XIXIXIXIX"'/\/,- /'-/'-;
'\
/'" /"'/'\ /'" /1XlXrxIXfX1XIXIXI'\ / '" / "'/"'/"'/
TRUSS GIRDER
,\. /\. /'\ /'\ /'\ /lXIXIXIXIXIXIXIXI"- / '\ / '\/ '\/'\/1I ~ I ~
I
SPECIAL SEGMENT ~
, , , .
,.- Inelastic Deformability :'~,~,~.
Energy Dissipation
-,-~., , ,'.'.' ,
4 41
/
//
3. /
5.
.Special ductile trusses. ..as part of moment frames
.Response factor. ..R = 6.5
.Height limitation in Seismic Zones 3 & 4 = 240 ft
33
-r--
I
"':"":k:::I-:-: ;-:~:r\K1 D ;-:a", .,Q. r:::1 ,+:trn;:A: I ",aXI STC~'A S "' R
~~
6.5..
~.~-~:
,6.0
\
~Columns (Piers)
/ ~M M
~
.~.::::.fu::.:.::I~:'
j~I:::i:::1
".
if[:!;:
:111\\. w<~
.~:'§jv1"Y
RT""c """,,":' " "
'R"" -
.::;::::::!'::[;~[c'
¥*:~Ii~~I~I
!i;~;1~j
;~~:j'i;;;::;.#;;!:~~:::::;:;t~~
1~\;:i~:~
:v
:i!i!~1:~~~:ji1~~::(~;::Ilif~!I~IfIll]
X/" f 'C T c"' "c,or c"' >c cc ", c'c. c
!iill~~'
62
1ii'
~z0
~a:UJ-JUJ0()~-J~a:t-OUJa..(/)
Ca
To Ts
PERIOD (SECONDS)
FIGURE 16..3-DESIGN RESPONSE SPECTRA
64
~'.'.;:,'
",.,:
!.~:~r c" Acc
:-;H
!:j::;~:;:i::::;::
:", ;.,:'f,:,':
~,~j;;~f~~~~Il,J
i*li~~~
':::::
t~[q~~i~
C
Uc
:~~w~~fJi1,f~;
ili~fk~'
1:~':::~~~:j;::;ilf;~;
and more recent data
t
-7 SF
;:*,':::
AVERAGE SOIL PROPERTIES FOR TOP 100 FEET(30 480 rom) OF SOIL PROFILE
SOILPROFILE
TYPE
SOIL PROFILENAME/GENERICDESCRIPTION Shear Wave
Velocity in ftfsec
(m/sec)
Standard PenetrationI
Test, N [or NCHforcohesionless soil
ii layers] (blows/foot)
Undrained ShearI
Strength pst(kPa)
SA Hard Rock > 5,000
(1,500)
Sa Rock 2,500 to 5,000(760 to 1,500)
:_.cr::::::J
.,6
.~
.~..~
.~~a~~~.~~.~I~I~I~
~~'~~
Sc Very Dense Soil andI Soft Rock
1,200 to 2,500(360 to 760)
> 50 > 2,000
(100)
So Stiff Soil Profile 600 to 1 ,200(180 to 360)
15 to 50 1,000 to 2,000(50 to 100)
SE1 Soft Soil Profile < 600( 1 80)
< 15 < 1,000
(50)
SF~~",.
Soil Requiring Site-specific Evaluation. See Section 1629.3.1.
!~;.; ,t!~ .! ;;;,.e::st,.~:-:,._.~-
69
.
0
,"','~~1
;1
1 Site-specific geotechnical investigation and dynamic site response analysis shall be
performed to determine seismic coefficients for Soil Profile Type SF-
!:::!: ~ ll~~[1l~ \l~1 ~ ~ ~ ~ ~ l~ ~~ ~ ~ j ~ ~iii~ji1 ~ ~~ ~ 1:
;::::
..'.
T¥PE::j\::I[...
~;~:~ ,~(~j
i(!~1.~~~~\~ri\:iojQ&:i:::i:[:~::\~:r\
-6~
~]92
T~ METHOD A
~~
vMETHOD B
I~"-
t'""""'
.~
I:
~~..1~~~I~I~-,-~~
(~- 'jif
~
I~-~~I ~
-,~~-':::1~1-""Cl-!j-~~--
~I :...~~~'
I~I '~'/ ",-~~.~c.'/
I " Ji;~"!~
Fx = (V -Ft )~~..~ ~
Lwh
T :::; 0.7 sec. ...Ft = 0
T > 0.7 sec. ...Ft = 0.07 T V ~ 0.25V
Ft = O.O7TV Fnn r"=:J[~~~~~~~ J[=~~= ~-
~==~~~~=] [=~=~~= I
\ r\ I\ /.I ~I.I
\ I\ ~,\ I\ I\ I
\
hn
i I ~~==~~~J [==~~~=\ F x ! I ~~~;~=J [=~=~=r \~X \ ~ =~~==J [~=~~~=J [~~~~~~~:=
\ f ==~~~~~~J [=~=~~J [~=~~=
h x \ "1 ==~~~~~J [=~~~~=J [~~~=~=\~
U =~~~~~~~J [~~=~~~=] I
\ ! ., , , "'===~~~~~ J[==~~~~~ J ,,[==~~= = , , , ,'""""""""""""""""""""""""""""""" """"""""""""""""""",,"":-:-:-:-:-:-:-:-:-:-:-:-:-:-:-:-:-:-:-:-:-:-:-:-:-:-:-:-:-:-:-:-:-:-:-:-:-:-:-:-:-:-:-:-:-:-:-:-:-:-:-:-:-:
v
Fthn
109
.
force-resisting system
in proportion
to their
Distribute
story shear
to elements
of lateral
Horizontal
of
Sec
"Story" 1630.6
Distribution
Shear
~
rigidities. ..considering
diaphragm
rigidity
Ev+
-It=:> +
E -
motion. .."vertical acceleration effect"
-p
,t\
124
~ ;,c ;;~.f
-,.=~E
t~~~,~~~
~~~~~
~b~~~~
~i;~l~~~L_.~~
~~[~I~I~I~~I~I~I~~I~~I ~M~
~~,?' ;t~1- :~ r..",,"1"), "
'/" E \I
v~;
0.90 ::t:
(30 -3)rmax ~AB
1.5~ <
128
II P II &
rmax
rmax
.:':';'..,~:.;;:
...;:f.:-.-"'.;:
~~
129
V!/2 Vt4V!/2 V!/4
:'.~~
Vt2 Vt2 Vt/2p(min) = 1.0
V!/2
rmax
rmax
131
"P" &
Assume rmax = rmaxi
Perimeter frames (SMRF) located
along both orthogonal axes of building.
6 bays @ 25' each direction
Assume center of mass & center
of rigidity located at geometric center.
For illustrative purposes, ignore
accidental torsion.
rmax = 0.5
1 .73 *
1.4 *p =
rmax = (0.70)(Vs/8 + Vs/8)/Vs
rmax = 0.175
1.24p =
rmax
,)
~
~~.2'",ir,
133
"P "
Perimeter braced frames located
along both orthogonal axes of building.
6 bays @ 25' each direction
Assume center of mass & center
of rigidity located at geometric center.
For illustrative purposes, ignore
accidental torsion.
All braced frames identical in configuation
1 braced frame each side
rmax = 0.25
rmax = 0.125
--~17\:\~~/7\\~-Vs/4 Vsl8Vs/8 1.0pmin =
elements. ..
shearwalls
frames
>
i'
ii :I CI 'I '
135
r 90' 1
60'
-
1.40u =
u =
u =
u =
u =
** See Appendix. .."Design of Reinforced Concrete Buildings under the 1997 VBG"
by S.K. Ghosh, May-June issue of Building Standards magazine
140
u = 1 .40 + 1. 7L
u =
= 0.90flexure.. .0
shear. ..0 = 0.85
