UBC 97 Summary

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\![:i:11i

~~

::::::::,

lifff11;fj1i!i~f~1ii1jpii1\~:

1 Site-specific geotechnical investigation and dynamic site response analysis shall be

performed to determine seismic coefficients for Soil Profile Type SF-

-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