Concrete Column Base Fasteners Near Two Edges
Based on ACI 31802
















INPUT
DATA & DESIGN SUMMARY











CONCRETE STRENGTH

f_{c}'

=


ksi








SPECIFIED STRENGTH
OF FASTENER

f_{ut}

=


ksi








???????? (The strength of most fastenings is
likely to be controlled by the embedment strength rather







???????? than the steel strength, so it is
usually economical to use ASTM A307 Grade A fastener.)







FACTORED COLUMN
AXIAL LOAD

P_{u}

=


k








FACTORED TOTAL
BASE SHEAR LOAD

V_{u}

=


k








FACTORED COLUMN
MOMENT

M_{u}

=


ftk








EFFECTIVE
EMBEDMENT DEPTH

h_{ef}

=


in








FASTENER DIAMETER

d

=


in








FASTENER HEAD TYPE












?? ( 1=Square, 2=Heavy Square, 3=Hex, 4=Heavy
Hex, 5=Hardened Washers )








FASTENER
CENTERTOCENTER SPACING

s

=


in








DIST. BETWEEN
FASTENER & EDGE

c1

=


in








DIST. BETWEEN
FASTENER & EDGE

c2

=


in














































ANALYSIS














NUMBER OF
GOVERNING FASTENERS

n

=









MAX TENSION ON
GOV'G FASTENERS


N_{u} = M_{u}/s  P_{u}/2 =


k







SHEAR FORCE ON
GOV'G FASTENERS


V_{u} = V_{u, total }/ 2 =


k







EFFECTIVE AREA OF
ONE FASTENER


A_{se}

=


in^{2}







BEARING AREA OF
ONE HEAD

A_{b}

=


in^{2}, ( or determined from manufactures's catalogs.)



CHECK THE
GOVERNING FASTENERS TENSILE STRENGTH :



























=


k


N_{u}






















where :

f

=













CHECK CONCRETE
BREAKOUT STRENGTH OF GOVERNING FASTENERS :






















































=


k


N_{u}









where :

f

=














???????????? y_{1} term is 1.0 for no
eccentricity in the connection.










???????????? y_{3} term is 1.0 for
location where concrete cracking is likely to occur.



































=


k


N_{u}






















where :

f

=














???????????? y_{4} term is 1.0 for
location where concrete cracking is likely to occur.







CHECK SIDEFACE
BLOWOUT STRENGTH :











c_{min}

>

0.4h_{ef}













Since the fasteners are located far from a free
edge of concrete, c>0.4h_{ef} ,this type of failure mode is not applicable.



DETERMINE DESIGN
TENSILE STRENGTH OF GOVERNING FASTENERS :




























=


K























CHECKGOVERNING
FASTENERS SHEAR STRENGTH :



























=


k


V_{u}






















where :

f

=




































































=


k


V_{u}









where :

f

=














???????????? y_{5} term is 1.0 for no
eccentricity in the connection.










???????????? y_{7} term is 1.0 for
location where concrete cracking is likely to occur.








???????????? l term is load bearing length of the anchor for shear, not to
exceed 8d.




























































=


k


N_{u}









where :

f

=

0.75













???????????? y_{3} term is 1.0 for
location where concrete cracking is likely to occur.








k_{cp}

=


for h_{ef} > 2.5 in.










DETERMINE DESIGN
TENSILE STRENGTH OF GOVERNING FASTENERS :




























=


K























REQUIRED EDGE
DISTANCES AND SPACINGS TO PRECLUDE SPLITTING FAILURE :








Since
headed castinplace fasteners are not like to be highly torqued, the minimun
cover requirements of ACI 318 Sec. 7.7 apply.


Cover_{Provd}

>

Cover_{Reqd}


[Satisfactory]









CHECK TENSION AND
SHEAR INTERACTION OF GOVERNING FASTENERS :









Since

N_{u}


0.2 f N_{n}

and












V_{u}


0.2 f V_{n}































































































Summary of Dimensional
Properties of Fasteners











Effective












Fastener

Gross

Area of

Bearing Area of Heads,
Nuts, and Washers







Diameter

Area of

Threaded

( A_{b} )?? ( in^{2} )







( in )

Fastener

Fastener

Square

Heavy

Hex

Heavy

Hardened









( in^{2 })

( in^{2 })

Square

Hex

Washers












































































??Techincal Reference:











??1. Ronald Cook, "Strength
Design











?? of Anchorage to Concrete,"
PCA,











?? 1999.





























































































???????? Note:















??????????????????
For seismic Design Category C, D, E or F, the design strength of
anchors shall be taken as 0.75 fN_{n} & 0.75fV_{n}.



??????????????????
(ACI31802 D3.3.3, IBC 1913.3.3)
















