Group of Concrete Anchors Tension Pull Away
Calculator 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
DESIGN LOAD


N_{u}

=


k








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 )







ECCENTRICITY



e

=


in








FASTENER
CENTERTOCENTER SPACING

s

=


in








DIST.
FR. THE OUTER FASTENERS TO EDGE

c

=


in























ANALYSIS










TOTAL
NUMBER OF FASTENERS

n

=










EFFECTIVE
AREA OF FASTENER

A_{se}

=


in^{2}








BEARING
AREA OF HEAD


A_{b}

=


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



CHECK
HIGHTEST TENSILE STRENGTH :






























=


k





=


















where :

f

=













CHECK
CONCRETE BREAKOUT STRENGTH :























































































=


k


N_{u}









where :

f

=














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







CHECK
PULLOUT STRENGTH OF SINGLE STUD :





























=


k


N_{u,
max, 1 stud}





















where :

f

=














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







EVALUATE
SIDEFACE BLOWOUT :












c


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.



REQUIRED
EDGE DISTANCES AND SPACINGS TO PRECLUDE SPLITTING FAILURE :









Since a welded, headed
fastener is not torqued, the minimun cover requirements of ACI 318 Sec. 7.7
apply.





Cover_{Provd}


Cover_{Reqd}



























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)
















