Anchorage to Concrete per ACI 318-08 Appendix D and IBC 2006

ACI 318-08, Appendix D IBC 2006 Section 1912 Anchorage to Concrete Mark Bartlett, PE Field Engineer Simpson Anchor Systems

Presentation Topics

• •

Brief ief His Histtory ory of of An Ancho chor De Design ign ACI 318-08, Appendix D • • • • • • •

• • • •

Design Equations Phi () Factors Interaction Equation Seismic Provisions Rein Reinfo forc rcem emen entt to to Pre Preve vent nt Brea Breako kout ut Other Issues Edge Edge Dis Dista tanc nces es,, Thi Thick ckne ness sses es & Spa Spaci cing ngs s

When to design per App. D IBC 2006 Adhesive ive Anc Anch hors and Co Concret rete Screws The Fu Future of of An Anchor De Design

Prior to ACI 318-02

• Cast-I Cast-In-P n-Plac lace e anchor anchors s covered covered by: by: – PCI / ACI 349 – UBC / IBC codes listed allowable stress capacities capacities for for CIP bolts

Prior to ACI 318-02

• Design Design of of Post-In Post-Insta stalle lled d anchor anchors: s: – Individual manufacturers supplied supplie d load values based on testing – Values found in catalogs and ICBO/ICC reports – Methodology was allowable stress and assumed assumed an uncrack uncracked ed and unreinfo unreinforced rced sectio section. n.

Prior to ACI 318-02

• Cast-I Cast-In-P n-Plac lace e anchor anchors s covered covered by: by: – PCI / ACI 349 – UBC / IBC codes listed allowable stress capacities capacities for for CIP bolts

Prior to ACI 318-02

• Design Design of of Post-In Post-Insta stalle lled d anchor anchors: s: – Individual manufacturers supplied supplie d load values based on testing – Values found in catalogs and ICBO/ICC reports – Methodology was allowable stress and assumed assumed an uncrack uncracked ed and unreinfo unreinforced rced sectio section. n.

ACI 318-08, Appendix Appendix D

ACI 318, Appendix D

• Stre Streng ngth th desi design gn meth method od for for anchorage to concrete (i.e. Nua  Nn or Vua  Vn) – Cast-In-Place (CIP) anchors – Post-Installed (PI) anchors • Under Undercu cutt anchor anchors s • Torque-c Torque-contr ontrolle olled d anchors anchors • Deformat Deformationion-con control trolled led anchors anchors

– PI anchors must be prequalified per ACI 355.2

Appendix D Design Equations & Failure Modes

• Desi Design gn equat equation ions s chec check k5 different failure modes – Steel capacity capacity • Tens Tensio ion n and and Shea Shear r

– Concrete breakout breakout capacity • Tens Tensio ion n and and Shea Shear r

– Pullout/Pull-throug Pullout/Pull-through h capacity capacity • Tens Tensio ion n only only

– Concrete Pryout • Shea Shearr only only

– Concrete side-face blowout • Tensio Tension n and and CIP CIP only. only.

Appendix D Design Equations Equations

Design Equations

Tension Capacities Nsa = nAse,Nf uta Ncb = ANc/ANco(ec,Ned,N c,N cp,NNb) Npn = c,PNp Nsb = (160ca1 Abrg)f’c Shear Capacities Vsa = n 0.6 A se,V f uta Vcbg = AVc/AVco(ec,Ved,V c,V h,VVb) Vcpg = kcpNcbg

Steel Strength in Tension

Steel Strength In Tension – D.5.1

Nsa = nAse,Nf uta (Eq. D-3)

– Nsa – Nominal tensile strength of an anchor group – n – Number of anchors – Ase,N – Effective cross sectional area of anchor in tension – f uta – Specific ultimate tensile strength of anchor

Concrete Breakout Strength in Tension

Concrete Breakout In Tension – D.5.2

Ncb=ANc/ANco(ec,Ned,N c,N cp,NNb) (Eq. D-5)

• Ncb – Concrete breakout strength in tension


Ncb= ANc/ANco(ec,Ned,N c,N cp,NNb) • ANc – Projected failure area of group • ANco = 9 hef 2 Projected failure area of one anchor (Eq. D-6)


Ncb=ANc/ANco(ec,Ned,N c,N cp,NNb) 

Modification for eccentric load



ec,N =

1/[1+(2e’N/3hef )]

(Eq. D-9)

N

Centroid of anchors

T3

T2

e’N

T1

Resultant tension load







Modification for edge effects

If ca,min > 1.5hef then: Eq. D-10 ed,N = 1.0

ca

If ca,min < 1.5hef then: Eq. D-11 ed,N = 0.7 + 0.3 (ca,min / 1.5hef )



Modification for cracking 

c,N =1.4

for uncracked section if kc = 17 in eq. (D-7)



c,N per



c,N =1.0

evaluation report (ER) if kc from ER used in eq. (D-7) for cracked section




Ncb=ANc/ANco(ec,Ned,Nc,Ncp,NNb)



cp,N –







Modification for Post-Installed anchors 

Uncracked concrete



No supplemental reinf. to control splitting

If ca,min > cac then: cp,N = 1.0 (Eq. D-12) If ca,min < cac then: cp,N = ca,min/cac (Eq. D-13) Where cac= 2.5 hef (undercut anchors) 4 hef (wedge anchors)


Ncbg=ANc/ANco(ec,Ned,Nc,Ncp,NNb) • Basic concrete breakout strength • Nb=kc  f’c hef 1.5 (Eq. D-7) – kc – Coefficient for basic concrete breakout strength • Found in either App. D or per product ER

–  – Modification factor for lightweight concrete – f’c – Concrete compressive strength – hef – Effective embedment depth • Tested hef found in manufacturer’s catalog or product ER

Pullout Strength in Tension

Pullout Strength In Tension – D.5.3

Npn = c,PNp

(Eq. D-14)

• Npn – Nominal pullout strength •

c,P –

Modification for cracking

– 1.0 for cracked – 1.4 for uncracked

• Np – Pullout strength in tension

Pullout Strength In Tension – D.5.3

Npn = c,P Np

(Eq. D-14)

• Np – Pullout strength in tension • For PI anchors Np based on ACI 355.2 test results • For CIP anchors, Np based on: – Np = 8 Abrgf’c – Np = 0.9f’cehda

(Eq. D-15)

headed bolts

(Eq. D-16)

hooked bolts

Side-Face Blowout Strength in Tension

Side-Face Blowout Strength – D.5.4

Nsb = (160ca1 Abrg)f’c (Eq. D-17) • Nsb – Side-face blowout strength (headed anchors only) • ca1 – edge distance • Abrg – Net bearing area of the head of anchor •  – Modification factor for lightweight concrete

Steel Strength in Shear

Steel Strength In Shear – D.6.1

• Vsa = n Ase,V f uta (eq. D-19)

CIP HSA

• Vsa = n 0.6 Ase,V f uta (eq. D-20) – n – number of anchors – Ase,V – effective cross sectional area of a single anchor in shear – f uta – specified tensile strength of anchor steel

Steel Strength In Shear – D.6.1

• Vsa may also be based on the results of tests performed and evaluated according to ACI 355.2

Concrete Breakout Strength in Shear

Concrete Breakout Strength In Shear – D.6.2

Vcbg = AVc/AVco(ec,Ved,V c,V h,VVb) (Eq. D-22)

• Vcbg – Concrete breakout strength in shear


Vcbg = AVc/AVco(ec,Ved,Vc,V h,VVb) – AVc – projected concrete failure area of a group of anchors V

1

c a

ha 1.5ca1

s1

ca2

AVc

AVc = (1.5ca1 + s1 + ca2) ha


Vcbg = AVc /AVco(ec,Ved,Vc,V h,VVb) – AVco – maximum projected concrete failure area of a single anchor AVco = 4.5 ca12 (Eq. D-23) 1

c a

V

1.5c1 1.5ca1 1.5ca1

AVco

Concrete Breakout In Shear – D.6.2

Vcbg = AVc/AVco(ec,Ved,Vc,V h,VVb) 

ec,V –

load

Modification for eccentric

(Eq. D-26)



ed,V – 

Modification for edge effects

If ca2 > 1.5ca1 then



ed,V =

1.0 (Eq. D-27) V

If ca2 < 1.5ca1 then

ed,V =

(Eq. D-28)

0.7 + 0.3ca2/1.5ca1

ca1 ca2



c,V Modification

factor for

cracking 

c,V =

1.4 for anchors located in a region where analysis indicates no cracking at service loads



Who is currently doing this analysis?



c,V =

1.0 for anchors in cracked concrete with no supplemental reinforcement or edge reinforcement smaller V than a #4 bar <#4



c,V =

1.2 for anchors in cracked concrete with reinforcement of a #4 bar or greater between the anchor and the edge V

>#4



c,V =

1.4 for anchors in cracked concrete with reinforcement of a #4 bar or greater between the anchor and the edge, and with the reinforcement enclosed V within stirrups spaced at not more than 4”.

#4

#4@4”



h,V –



h,V =  1.5ca1/ha



Modification factor for shear strength of anchors located in concrete members with ha < 1.5ca1 but not less than 1.0

When ha < 1.5ca1, AVc is reduced. However, breakout strength is not directly proportional to member thickness. h,V adjusts for this.

1

c a

1.5c1

V

ha


Vcbg = AVc/AVco(ec,Ved,Vc,V h,VVb) • Vb=(7(e /da)0.2 da) f’c (ca1)1.5

(Eq. D-24)

– e – load bearing length of anchor • Same as hef if there is no sleeve on anchor • Per manufacturer if there is a sleeve

– da – outside diameter of anchor –  – adjustment for lightweight concrete – f’c – concrete compressive strength – ca1 – edge distance

Pryout Strength in Shear

Concrete Pryout Strength In Shear – D.6.3

Vcpg = kcpNcbg

(Eq. D-30)

•

kcp = 1.0 for hef < 2.5”

•

kcp = 2.0 for hef > 2.5”

•

Ncbg – Nominal concrete breakout strength in tension – Always do tension calcs first

Phi () Factors

Phi () factors

• Nua  Nn or Vua  Vn • Phi () factors are applied to nominal capacities before comparing with factored forces • Based on: – Supplemental reinforcement – Failure mode – Load type – Anchor property

Phi () factors D.4.4 

Failure Mode

Anchor Property

Condition A Tension

Condition B

Shear

Ductile Steel

Tension

Shear

0.75

0.65

0.65

0.60

Use Condition B Brittle

Side Face Blowout

Factor

CIP

0.75

0.75

0.70

0.70

CIP

0.75

0.75

0.70

0.70

Cat. 1

0.75

0.75

0.65

0.70

Cat. 2

0.65

0.75

0.55

0.70

Cat. 3

0.55

0.75

0.45

0.70

CIP

0.70

0.70

Cat. 1

0.65

0.70

Cat. 2

0.55

0.70

Cat. 3

0.45

0.70

CIP

0.70

0.70

Cat. 1

0.65

0.70

Cat. 2

0.55

0.70

Cat. 3

0.45

0.70

Breakout

Pullout

Use Condition B

Pryout

Use Condition B

Supplemental Reinforcing D.4.4 • Condition A – Applies where supplementary reinforcement is present except for pullout and pryout strengths. • Condition B – Applies where supplementary reinforcement is not present, and for pullout or pryout strength.

Supplemental Reinforcing

• Supplemental Reinforcement – Reinforcement that acts to restrain the potential concrete breakout but is not designed to transfer the full design load from the anchors into the structural member. – Refer to sections D.5.2.9 and D.6.2.9 for full design load transfer requirements

Interaction of Tension and Shear

Interaction of Tension and Shear – D.7

Interaction of Tension and Shear – D.7

• If Vua0.2Vn full tension allowed – Ignore Shear

• If Nua0.2Nn full shear allowed – Ignore Tension

• Otherwise Nua + Vua

Nn

< 1.2

Vn

Appendix D Seismic Provisions

Seismic Provisions

D.3.3 – When anchor design includes earthquake forces for structures assigned to Seismic Design Category C, D, E, or F , the additional requirements of D.3.3.1 through D.3.3.6 shall apply.

D.3.3.1 – The provisions of Appendix D do not apply to the design of anchors in plastic hinge zones 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 in accordance with ACI 355.2. Pullout strength N p and steel strength of the anchor in shear V sa shall be based on the results of the ACI 355.2 Simulated Seismic Tests.

Seismic Provisions

D.3.3.3 – The anchor design strength associated with concrete failure modes shall be taken as 0.75 N n and 0.75 V n, where  is given in D.4.4 or D.4.5, and N n and V n 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.

• 0.75 reduction to concrete capacity in Seismic Design Category C – F • Impractical to prove concrete remains uncracked

Seismic Provisions

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 connecting to the structure shall be designed so that the attachment will undergo ductile yielding at a force level 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 and D.3.3.5, it shall be permitted 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 walls, it shall be permitted to take the design strength of the anchors as 0.5 times the design strength determined in accordance with D.3.3.3.

Seismic Provisions

• Summary – Seismic Design Category C, D, E & F – No anchors in plastic hinge – PI anchors must pass Simulated Seismic Test – Design strength reduced by 25% – Ductile steel failure of anchors shall control, or... – Ductile yielding of attachment, or... – Anchor capacity reduced by 60%

Seismic Provisions

• Seismic and edge effects – At small edge distances, concrete breakout (non ductile failure mode) will often control – If attachment will not experience ductile yielding before breakout occurs, then 40% anchor capacity reduction unless... – Reinforce section to prevent breakout from occurring

Reinforcement to Prevent Concrete Breakout


D.4.2.1 – The effect of reinforcement provided to restrain the concrete breakout shall be permitted to be included in the design models used to satisfy D.4.2. Where anchor reinforcement is provided in accordance with D.5.2.9 and D.6.2.9, calculation of the concrete breakout strength in accordance with D.5.2 and D.6.2 is not required.

D.5.2.9 – Where anchor reinforcement is developed in accordance with Chapter 12 on both sides of the breakout surface, the design strength of the anchor reinforcement shall be permitted to be used instead of the concrete breakout strength in determining N n. A strength reduction factor of 0.75 shall be used in the design of the anchor reinforcement.


• Refer to Commentary RD.5.2.9 for more information

Reinforcement to Prevent Concrete Breakout D.6.2.9 – Where anchor reinforcement is either developed in accordance with Chapter 12 on both sides of the breakout surface, or encloses the anchor and is developed beyond the breakout surface , the design strength of the anchor reinforcement shall be permitted to be used instead of the concrete breakout strength in determining V n. A strength reduction factor of 0.75 shall be used in the design of the anchor reinforcement.

Plan

Section

• Refer to Commentary RD.6.2.9 for more info


t n s e a m e e v c r i t o c f e i f n f e e r s r r o a h B c n a

Edge Reinforcement Anchor Reinforcement

Section

Plan

• Refer to Commentary RD.6.2.9 for more info


• Per Commentary RD.5.2.9 and RD.6.2.9: – “As a practical matter, use of anchor reinforcement is generally limited to cast-in-place anchors.”

• What about post-installed anchors? – At small edge distances, anchor capacity will be greatly reduced for seismic design.

Other Appendix D Issues

Capacity Adjustments • PI anchor pullout capacity – Tested values of Np are done in 2500 psi concrete – Pullout capacities increase for higher f’ c – Adjustment equations in ER

• Grout pads – 20% reduction in shear strength (D.6.1.3) – App. D makes no mention to grout pad thickness

• Shear load parallel to concrete edge – Breakout capacity doubled per D.6.2.1(c).

Triple Edge Conditions

D.5.2.3 – Where anchors are located less than 1.5hef from three or more edges, the value of hef used in Eq. (D-4) through (D-11) shall be the greater of c a,max /1.5 and one-third of the maximum spacing between the anchors within the group.

D.6.2.4 – Where anchors are influenced by three or more edges, the value of c a1 used in Eq. (D-23) through (D-29) shall be the greatest of c a2 /1.5 in either direction, ha /1.5; and one-third of the maximum spacing between the anchors within the group.

Triple Edge Condition in Tension

Triple Edge Condition in Shear

Corner Condition D.6.2.1(d)

(d) For anchors located at a corner, the limiting nominal concrete breakout strength shall be determined for each edge, and the minimum value shall be used.

V V ca1

ca2 ca1

ca2

Shear Near an Edge D.6.2.1 Where anchors are located at varying distances from the edge and the anchors are welded to the attachment so as to distribute the force to all anchors, it shall be permitted to evaluate the strength based on the distance to the farthest row of anchors from the edge. In this case, it shall be permitted to base the value of ca1 on the distance from the edge to the axis of the farthest anchor row that is selected as critical, and all of the shear shall be assumed to be carried by this critical anchor row alone.

Anchors welded to plate

V

0.5V

0.5V

ca1 ca1

Anchors not welded to plate

Shear Near an Edge D.6.2.1

• Increase ca1 without welding to plate – Slot holes closest to edge

V ca1

Required Edge Distances, Spacings, and Thicknesses

Section D.8

Minimum spacings and edge distances for anchors and minimum thicknesses of members shall conform to D.8.1 through D.8.6, unless supplementary reinforcement is provided to control splitting. Lesser values from product-specific tests performed in accordance with ACI 355.2 shall be permitted. D.8.1 – Unless determined in accordance with D.8.4, minimum center-to-center spacing of anchors shall be 4d a for untorqued cast-in anchors, and 6d a for torqued cast-in anchors and post-installed anchors. D.8.2 – Unless determined in accordance with D.8.4, minimum edge distances for cast-in headed anchors that will not be torqued shall be based on specified cover requirements for reinforcement in 7.7. For castin headed anchors that will be torqued, the minimum edge distances shall be 6d a.

Section D.8

D.8.3 – Unless determined in accordance with D.8.4, minimum edge distances for post-installed anchors shall be based on the greater of specified cover requirements for reinforcement in 7.7, or minimum edge distance requirements for the products as determined by tests in accordance with ACI 355.2, and shall not be less than 2.0 times the maximum aggregate size. In the absence of product-specific ACI 355.2 test information, the minimum edge distance shall be taken as not less than: Undercut anchors.................................................. 6d a Torque-controlled anchors..................................... 8d a Displacement-controlled anchors......................... 10d a

Section D.8

D.8.4 – For anchors where installation does not produce a splitting force and that will remain untorqued, if the edge distance or spacing is less than those specified in D.8.1 to D.8.3, calculations shall be performed by substituting for d a a smaller value d’a that meets the requirements of D.8.1 to D.8.3. Calculated forces applied to the anchor shall be limited to the values corresponding to an anchor having a diameter of d’ a. D.8.5 – The value of h ef for an expansion or undercut post-installed anchor shall not exceed the greater of 2/3 of the member thickness and the member thickness minus 4 in.

Section D.8

D.8.6 – Unless determined from tension tests in accordance with ACI 355.2, the critical edge distance, c ac , shall not be taken less than: Undercut anchors............................................... 2.5hef Torque-controlled anchors.................................... 4hef Displacement-controlled anchors.......................... 4hef

Limitations of Appendix D

• Applies for CIP and some PostInstalled anchors – Specialty inserts, through bolts, adhesive anchors, screw anchors, PAT fasteners outside scope of Appendix D – ACI Commentary: “Adhesive anchors are widely used and can perform adequately. At this time…outside the scope.”


• NW Concrete and LW Concrete only – Reductions in capacity in LW – CMU and Concrete on metal deck outside scope of App. D • Grouted CMU will still use existing postinstalled anchor products


• Limits to: – Diameter (2”) – Embedment depth (25”) – Concrete compressive strength (8000 psi PI; <10000 psi CIP).

When to Use Appendix D

When to use Appendix D

• Per ACI 318-08, D.2.1 – “…anchors in concrete used to transmit structural loads by means of tension, shear, or a combination of tension and shear between (a) connected structural elements; or (b) safety-related attachments and structural elements.” – What is a “safety-related attachment”?

When to use Appendix D

• Per ACI 318-08, RD.2.1 – Commentary lists examples for safetyrelated attachments. – “…safety-related attachments that are not part of the structure (such as sprinkler systems, heavy suspended pipes, or barrier rails) are attached to structural elements.” – Will sprinkler systems be attached with cracked concrete anchors?

When to Use Appendix D IBC 2006

IBC 2006, Section 1911

Anchorage To Concrete – Allowable Stress Design 1911.1 Scope. The provisions of this section shall govern the allowable stress design of headed bolts, and headed stud anchors cast in normal-weight concrete for purposes of transmitting structural loads from one connected element to the other. These provisions do not apply to anchors installed in hardened concrete or where load combinations include earthquake loads or effects. The bearing area of headed anchors shall be not less than one and one-half times the shank area. Where strength design is used, or where load combinations include earthquake loads or effects, the design strength of anchors shall be determined in accordance with Section 1912. Bolts shall conform to ASTM A 307 or an approved equivalent.

IBC 2006, Section 1912 Anchorage To Concrete – Strength Design 1912.1 Scope. The provisions of this section shall govern the strength design of anchors installed in concrete for purposes of transmitting structural loads from one connected element to the other. Headed bolts, headed studs and hooked (J- or L-) bolts cast in concrete and expansion anchors and undercut anchors installed in hardened concrete shall be designed in accordance with Appendix D of ACI 318 as modified by Section 1908.1.16, provided they are within the scope of Appendix D. Exception: Where the basic concrete breakout strength in tension of a single anchor, Nb, is determined in accordance with Equation (D-7), the concrete breakout strength requirements of Section D.4.2.2 shall be considered satisfied by the design procedures of Sections D.5.2 and D.6.2 for anchors exceeding 2 inches (51mm) in diameter or 25 inches (635mm) tensile embedment depth.

The strength design of anchors that are not within the scope of Appendix D of ACI 318, and as amended above, shall be in accordance with an approved procedure.

IBC 2006, Section 1908 Modifications to ACI 318 1908.1.16 ACI 318, Section D.3.3. Modify ACI 318, section D.3.3.2 through C.3.3.5, to read as follows:

D.3.3.2 – In structures assigned to Seismic Design Category C, D, E or F, post-installed anchors for use under D.2.3 shall have passed the Simulated Seismic Tests of ACI 355.2 . D.3.3.3 – In structures assigned to Seismic Design Category C, D, E or F, the design strength of anchors shall be taken as 0.75 N n and 0.75V n, where  is given in D.4.4 or D.4.5, and N n and V n are determined in accordance with D.4.1. D.3.3.4 – In structures assigned to Seismic Design Category C, D, E or F, anchors shall be designed to be governed by tensile or shear strength of a ductile steel element , unless D.3.3.5 is satisfied. D.3.3.5 – Instead of D.3.3.4, the attachment that the anchor is connecting to the structure shall be designed so that the attachment will undergo ductile yielding at a load level corresponding to anchor forces no greater than the design strength of anchors specified in D.3.3.3, or the minimum design strength of the anchors shall be at least 2.5 times the factored forces transmitted by the attachment.

Adhesive Anchors and Concrete Screws

Adhesives Anchors and Concrete Screws

• IBC 2006, Section 1912 – “The strength design of anchors that do not within the scope of Appendix D of ACI 318…shall be in accordance with an approved design procedure.”

• What design procedures are approved? • Who decides?


• IBC 2006, Section 104.11 104.11 Alternative materials, design and methods of construction and equipment. The provisions of this code are not intended to prevent the installation of any material or to prohibit any design or method of construction not specifically prescribed by this code, provided that any such alternative has been approved. An alternative material, design or method of construction shall be approved where the building official finds that the proposed design is satisfactory and complies with the intent of the provisions of this code, and that the material, method or work offered is, for the purpose intended, at least the equivalent of that prescribed in this code in quality, strength, effectiveness, fire resistance, durability and safety. 104.11.1 Research reports. Supporting data, where necessary to assist in the approval of materials or assemblies not specifically provided for in this code, shall consist of valid research reports from approved sources.


• IBC 2006, Section 104.11 – The building official has the ability to approve a material if it is not specifically referenced in the code – Adhesive anchors and screw anchors fall into this category – Caution: Most building officials are still learning about strength design provisions of anchors


• Many engineers are still designing adhesive anchors and screw anchors per ASD • Strength design code reports for adhesives and screws are just starting to come online


• ICC ES AC 193 – Expansion anchors – Undercut anchors – Screw anchors

• ICC ES AC 308 – Adhesive anchors

Code Reports

The Future of Anchors

• Reliance on software for anchor design • Many new post-installed anchors • Confusion among engineers, contractors and building officials • Lengthy transition period

Anchorage to Concrete per ACI 318-08 Appendix D and IBC 2006

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