Sheet1ACI318-08 APPENDIX D - ANCHORING TO CONCRETEVersion
1.5COMMENTARY & SUPPLEMENTAL CALCULATIONS
MADE BYDATEJob No.SummaryFailure TypeUtilization RatioCKD.
BYDATESheet No.Steel Failure (T)0.159Concrete Breakout
(T)0.653FORXYZ BaseplatePullout (T)0.113Side-face Blowout
(T)0.665CONCRETE ANCHOR DESIGN BASED ON ACI318-08 APPENDIX DSteel
Failure (V)0.097Basic Design Parameters: (SEC D.3-D.4)NOTES &
SKETCHESConcrete Breakout (V)0.523Loads:(Per Applicable Loads
Combinations in Sect. 9.2; load applications that areConcrete
Pryout (V)0.173predominantly high cycle fatigue or impact loads are
not covered.)Stress Ratio1.188Nua =34
TKA: Tension load, Nua, shall be factored per Section 9.2.1.
If anchors are located in Seismic Design Category C-F, Nua must
set as one of the following: 1. Steel Capacity Nua = n Ase Futa 2.
Attaching Member's Ductile Yielding Force, if less than anchor's
limits set in D.3.3.3. 3. Higher Factored force Nua = Nua,Previous
x 2.5 Nua = Nua,Previous x 2.0 (if anchoring stud bearing
wall).
NOTE: If concrete capacity is unable to accomodate anchors,
additional anchor reinforcement may be required. See "Tension
Reinf." or "Shear Reinf." worksheet, if necessary.kNUltimate
Factored Tensile Load (kN)Vua =18
TKA: Shear load, Vua, shall be factored per Section 9.2.1.
If anchors are located in Seismic Design Category C-F, Vua must
set as one of the following: 1. Steel Capacity Vua = n Ase Futa
(for cast-in headed stud) Vua = 0.6 n Ase Futa (others) 2.
Attaching Member's Ductile Yielding Force, if less than anchor's
limits set in D.3.3.3. 3. Higher Factored force Vua = Vua,Previous
x 2.5 Vua = Vua,Previous x 2.0 (if anchoring stud bearing
wall).
NOTE: If concrete capacity is unable to accomodate anchors,
additional anchor reinforcement may be required. See "Tension
Reinf." or "Shear Reinf." worksheet, if necessary.kNUltimate
Factored Shear Load (kN)Anchor Type:Number IdentifierJ or L
Bolt3
f Factor Conditions:Steel f Factor
Selection:TensionShearSelectionDuctile
DTaylor: Ductile: An element with a tensile test elongation of at
least 14 percent and reduction in area of at least 30 percent.
(Note: ASTM 307 is ductile.)
Brittle: An element with a tensile test elongation of less than
14 percent and reduction in area of less than 30 percent, or
both.Steel ElementDuctile0.750.650.750.65Brittle0.650.6Yes
DTaylor: Supplemental Reinforcement: Reinforcement that has a
configuration and placement similar to anchor reinforcement but is
not specifically designed to transfer loads from the anchors into
the structural member. Stirrups, as used in shear reinforcement,
may fall into this category.Potential Failure Surfaces crossed by
supplementary reinforcementproportioned to tie prism into the
structural member?Concrete f Factor Selection:J or L BoltAnchor
TypeNOTE: Hooks bolts are typically not a good design
practice.Condition ACondition BShear Loads0.750.70.75Category 1N/A
- Only applicable to Post-installed anchorsTension
LoadsCast-in:0.750.70.75Post-installedYesAnchor located in a region
of concrete member where analysis Category 10.750.65indicates no
cracking at service load levels? (YES = No Cracking
Anticipated)Category 20.650.55No
TKA: If Input is "Yes", anchor must meet the additional
requirements of Section D.3.3.1 through D.3.3.6.
D.3.3.1 - The provisions of Appendix D do not apply to the
design of anchors in plastic zone of concrete structures under
earthquake forces.
D.3.3.2 - Post-installed structural anchors shall be qualified
for use in cracked concrete and shall have passed the Simulated
Seismic Tests accordance with ACI 355.2. Pullout strength, Np, and
steel strength of the anchor in shear, Vsa, shall be based on the
results of the ACI 355.2 Simulated Seismic Tests.
D.3.3.3 - The anchor design strength associated with concrete
failure modes shall be taken as 0.75Nn and 0.75Vn, where is given
in D.4.4 or D.4.5, and Nn and Vn are determined in accordance with
D.5.2, D.5.3, D.5.4, D.6.2 and D.6.3, assuming the concrete is
cracked unless it can be demonstrated that the concrete remains
uncracked. (This spreadsheet accounts for factor in ouput.)
D.3.3.4 - Anchors shall be designed to be governed by the steel
strength of a ductile steel element as determined in accordance
with D.5.1 and D.6.1, unless either D.3.3.5 or D.3.3.6 is
satisfied.
D.3.3.5 - Instead of D.3.3.4, the attachment that the anchor is
connected to the structure shall be designed so that the attachment
will undergo ductile yielding at a force corresponding to anchor
forces no greater than the design strength of anchors specified in
D.3.3.3.
D.3.3.6 - As an alternative to D.3.3.4 & D.3.3.5, it shall
be permited to take the design strength of the anchors as 0.4 times
the design strength determined in accordance with D.3.3.3. For the
anchors of stud bearing wall, it shall be permitted to take the
design of the anchors as 0.5 times the design strength determined
in accordance with D.3.3.3.
Anchors are located in structure assigned to Seismic Design
Category C, D, E, or F. (Sect. D3.3)Category 30.550.45Concrete
Type:Number IdentifierNormalweightConcrete TypeNormalweight1
Steel strength of anchor in tension: (SEC D.5.1)
Nsa =nAsefutaAssumes no eccentricity in bolt group
loading(D-3)
n =4Number of Anchors in a GroupAse, N =1.23
TKA: See Table 1 for effective cross section area.in2Effective
Cross Sectional Area of Anchorfuta =58
DTaylor: Typical Anchors' Ultimate Strength (ksi)F1554-36
58F1554-55 75F1554-105 125A307 58ksiSpecified Tensile strength of
anchor steelValues used in design:fy =36
DTaylor: Typical Anchors' Yield Strength (ksi)F1554-36 36F1554-55
55F1554-105 105A307 36ksiSpecified Yield strength of anchor
steelfut =58
Nsa =285.36kf =0.75fNs =214.02k>Nu =34.00kOK
Concrete Breakout strength of anchor in tension: (SEC D.5.2)Ncb
=Anc Yed,NYc,NYcp,NNbSingle Anchor(D-4)Anco
Ncbg =Anc Yec,NYed,NYc,NYcp,NNbGroup of Anchors(D-5)Anco
Anc =1267.5in2Projected concrete failure area of anchor or group
of anchors. See RD.6.2.1(b)hef =12inEffective anchor embedment
depthca,min =11.5inThe smallest edge distanceca,max =200inThe
largest edge distancef'c=4000psie'N =0inEccentricity of Normal
Force on a group of anchor. See Figure RD.5.2.4Edges =1Number of
Edges surrounding anchor or group of anchors. See Figure RD.5.2.4
Commentarycac =12inCritical edge distance required to develop the
basic concrete breakout strength of a postinstalled anchor in
uncracked concrete w/o supplementary reinforcement to control
splitting.Anco =9hef2Projected area of the failure surface of a
single anchor remote from edges for ca,min of 1.5hef or
greaterYec,N =1< 1Modification factor for eccentrically loaded
anchor groups(1 + 2e'N) 3hefYed,N =1if Cmin > 1.5hef
Modification factor for edge effects=0.7 + 0.3 cminif Cmin <
1.5hef Modification factor for edge effects 1.5 hefYc,N =1.25for
Cast-in anchors in uncracked sectionYcp,N =1.00for Post-installed
anchors in uncracked section w/o supplemental reinforcementNb
=kclf'c1/2hef3/2Basic concrete breakout strengthk = 24 for cast-in
anchorNb =16lf'c1/2hef5/3Alternative concrete breakout strength for
11in < hef < 25in.
Anco =1296.0in2f =0.75Yec,N =1.00Yed,N =0.89Yc,N =1.25Ycp,N
=1.00Nb =63.70kNote: When an additional plate or washer is added at
the head of the anchor, it shall be permitted to calculate the
projected area of the failure surface by projecting the failure
surface outward 1.5hef from the effective perimeter of the plate or
washer. (Section D5.2.8)Ncbg =69.44kfNcb =52.08k>Nu
=34.00kOK
Pullout strength of anchor in tension: (SEC D.5.3)
Npn = Yc,PNpNOT ONE(D-14)Values used in design:Bearing area of
single headed stud or anchor bolt.See Table 1.k =24Abrg =2.24in2Y1
=1.00eh=3.0inDistance from the inner surface of the shaft to the
outer tip of the bolt. 3da 1.5Ca1 Modification factor for edge
effects=0.7 + 0.3 ca2 if Ca2 < 1.5Ca1 Modification factor for
edge effects 1.5 ca1l = 2*da =3.0inFor torque-controlled expansion
anchors with a distance sleeve separated from the expansion
sleeveYc,V =1.4Anchor in uncracked section
Yec,V =1.00f =0.75TABLE 2Yed,V =0.85Yc,V =1.40See code section
D.6.2.3 for alternative calculation of Vb.Yh,V =1.20Yh,V = (1.5ca1
/ ha) ^ 0.5 (where ha < 1.5ca1)Avco =288.00in2Values used for
designVb =18.60k11.5Ca1 =8inVcbg =45.88kYec,V =1fVcbg =34.41k>Vu
=18.00kOKYed,V =0.85Av =498
Concrete Pryout strength of anchor in shear: (SEC D.6.3)
Vcp =kcpNcbSingle Anchor(D-30)
Vcpg =kcpNcbgGroup of Anchors(D-31)
Kcp =1for hef < 2.5Kcp =2for hef > 2.5
Ncb g =69.44kf =0.75Vcpg =138.88kfVcpg =104.16k>Vua
=18.00kOKVua < 0.2fVnNONua <
0.2fNnSingleNOGroupNONua>0.2fNn & Vua>0.2fVnInteraction
of tensile and shear forces: (SEC D.7)Single1.720NGif Vua <
0.2fVnfNn > NUAN/AGroup1.188OK
if Nua < 0.2fNnfVn > VUAN/A
if Nua > 0.2fNn & Vua > 0.2fVnNUA+VUA