TO: PARTIES INTERESTED IN ANCHOR CHANNELS … · anchors connected to the back of the channel. ......

April 18, 2018

TO: PARTIES INTERESTED IN ANCHOR CHANNELS IN CONCRETE

ELEMENTS SUBJECT: Proposed Revisions to the Acceptance Criteria for Anchor Channels in

Concrete Elements, Subject AC232-0618-R1 (HS/VC).

Hearing Information: Tuesday, June 5, 2018 8:00 am Hilton Los Angeles Airport 5711 West Century Boulevard Los Angeles, CA 90045 (310) 410-4000

Dear Colleague: You are invited to comment on proposed revisions to AC232, which will be discussed at the Evaluation Committee hearing noted above. The proposed revisions to the criteria are based on a letter received from the Concrete and Masonry Anchor Manufacturers Association (CAMA), dated March 29, 2018 developed in conjunction with ICC-ES staff participation in the CAMA task group on AC232. The CAMA letter proposes revisions which may grouped into three topics as follows: 1. Addition of recognition for anchor channels with reinforcing bars instead of headed

anchors connected to the back of the channel. Proposed changes are in Annex A, Section 1.3, and Sections D.5.2.10, D.5.3.7, and D.5.4.3.

2. Changes to the interaction equations for seismic loading to follow ACI 318 requirements. Proposed changes are in Annex A, Sections D.7.4.2 and D.7.4.3.

3. Addition of a spacing requirement for anchor channels with I-shaped anchors oriented

longitudinal to the channel axis to permit proper concrete placement. Proposed changes are in Annex A, Section 1.3.4.7.

We are only posting the pages showing the proposed revisions as there were no changes to the rest of the criteria.

AC232-0618-R1

2

Should the committee approve the proposed revisions to the criteria, the ICC-ES staff will recommend a mandatory compliance date of December 15, 2018, with regard to proposed changes 2 and 3 above. This means that existing report holders, under this criteria, will need to show their compliance with the new provisions before the compliance date, or face mandated revisions of their reports. Report holders will be required to submit an application for editorial revision, along with appropriate fees, by no later than September 15, 2018. You are invited to submit written comments on this or any other agenda item, or to attend the Evaluation Committee hearing and present your views in person. If you wish to contribute to the discussion, please note the following: 1. Regarding written comments and presentations:

a. You should submit these via e-mail to [email protected] or by U.S. mail to the Western

Regional (Brea) office to be received by the applicable due date.

b. Comments are to be received by May 9, 2018. These written comments will be forwarded to the committee before the meeting, and will also be posted on the ICC-ES web site shortly after the deadline for submission. Written comments that are not submitted by this deadline will not be considered at the meeting.

c. Rebuttal comments, from the proponent noted in this letter, are to be received by May 18, 2018. They will be forwarded to the committee before the meeting, and will also be posted on the ICC-ES web site shortly after the deadline for submission. Written rebuttal comments that are not submitted by the deadline will not be considered at the meeting.

d. Visual presentations, in PowerPoint format only, are to be received by May 30, 2018. These will be forwarded to the committee before the meeting, and will also be posted on the ICC-ES web site shortly after the deadline for submission. Presentations that are not submitted by the deadline cannot be viewed at the meeting. Note: Videos will not be posted on the web site.

Presentations will be retained with other records of the meeting. It is the presenter’s responsibility, prior to the presentation, to verify with ICC-ES staff that the presentation files have been transferred satisfactorily to the presentation computer.

e. ICC-ES will post to the web site, on June 1, 2018, memos by the ICC-ES staff, responding to the previously received public comments.

f. If you miss the deadlines for submission of written comments and visual presentations, your verbal comments can be presented at the meeting.

g. Proposed criteria, written public comments, visual presentations, and responses by ICC-ES staff will be available at the meeting on a limited number of CDs for uploading to computers. ICC-ES will not provide any printed copies.

mailto:[email protected]

AC232-0618-R1

3

2. Regarding verbal comments and presentations:

Please plan to speak for not more than ten minutes. As noted above, visuals must be in PowerPoint format. We have a computer, projector, and screen available to those making visual presentations. It is the presenter’s responsibility, prior to their presentation, to verify with ICC-ES staff that presentation files have been satisfactorily transferred to the presentation computer.

3. Keep in mind that all materials submitted for committee consideration are part of the public record and will not be treated as confidential. It is the presenter’s responsibility to certify to ICC-ES staff that no materials infringe copyright.

4. Please do not communicate with committee members before the meeting about any items

on the agenda. We appreciate your interest in the work of the Evaluation Committee. If you have any questions, please contact me at (800) 423-6587, extension 3996, or Vincent Chui, P.E., S.E., at extension 3244. You may also reach us by e-mail at [email protected].

Yours very truly,

Howard Silverman, P.E. Senior Staff Engineer

HS/raf Encl. cc: Evaluation Committee

CONCRETE AND MASONRY ANCHOR MANUFACTURERS ASSOCIATION

Thomas Associates Executive Director

March 29, 2018

Vincent Chui ICC Evaluation Services, Inc. Western Regional Office 3060 Saturn Street, Suite 100 Brea, CA 92821

SUBJECT: Proposed revisions to the Acceptance Criteria for Anchor Channels in Concrete Elements (AC232)

Dear Vincent,

CAMA is writing to propose the following modifications to AC232:

Anchor channels with reinforcing bars instead of headed anchors connected to the back of the

channel (Section 1.3, Section D.5.2.10, D.5.3.7, D.5.4.3)

Interaction equations in case of earthquake loading (Section D.7.4.2 and D.7.4.3)

Minimum spacing in case of anchor channels with I-shaped anchors oriented longitudinally

(Section 1.3.4.7)

The rationale for these changes is provided below.

Item 1: Anchor channels with reinforcing bars instead of headed anchors connected to the back of the

channel (Section 1.3, Section D.5.2.10, D.5.3.7, D.5.4.3)

It is proposed to include anchor channels with deformed reinforcing bars connected to the channel profile

in AC232 (see Figure 1). Such channels are often used in curtain wall design in so-called front-of-slab

applications whereby the channel is installed in the face (edge) of the reinforced concrete slab. The use

of deformed reinforcing bars as the anchor elements of the anchor channel (as opposed to headed

anchors) is a structurally superior solution for this application provided that limitations on the application

are provided to a. ensure that the transfer of load from the reinforcing bars into the slab may be

characterized as a lap splice, and b. that concrete breakout failure will not occur. The determination of the

1300 Sumner Ave Cleveland, Ohio 44115 USA (T) +1 216‐241‐7333 (F) +1 216‐241‐0105

[email protected] www.concreteanchors.org

lap splice length is performed in accordance with ACI 318-11 Section 12.14 or ACI 318-14 Section 25.5

and no further design checks for the transfer of tension loads into the concrete are required.

Proposed modifications:

1.3 Anchor Channels Permitted Under This Acceptance Criteria:

1.3.1 Anchor Channel Assemblies: Anchor channels consist of a channel produced from hot-rolled or cold-formed

steel and at least two metal anchors on the channel web back as illustrated in Figure 1 and Figure 2 of this annex

whereby anchors may consist of round headed anchors, I-shaped anchors or deformed reinforcing bars.

The anchor channels shall be placed flush with the concrete surface as illustrated in Figure 3 of this annex. A fixture

shall be connected to the anchor channel by channel bolts (hammer head or hooked channel bolts) with nut and

washer in accordance with Figure 1 and Figure 3 of this annex.

1.3.4 Anchors: The headed anchors shall be produced from carbon or stainless steel. Deformed reinforcing bars

shall conform to (a), (b), (c), (d), (e), (f) or (g):

(a) ASTM A615 – carbon steel

(b) ASTM A706 – low-alloy steel

(c) ASTM A996 – axle steel and rail steel; bars from rail steel shall be Type R

(d) ASTM A955 – stainless steel

(e) A1035 – low-carbon chromium steel

(f) CAN/CSA-G30.18 – billet steel bars for concrete reinforcement

(g) DIN 488 – BSt 500– carbon steel

The anchors may be welded, forged or bolted to the channel. Where deformed reinforcing bars are welded, they shall

be of a weldable grade. All anchors attached to the anchor channel shall be of the same type, size and embedment.

1.3.4.1 Anchors that are welded to the channel may consist of I-shaped profiles, or round-headed anchors or

deformed reinforcing bars. The welding shall be performed by any appropriate welding method in accordance with

AWS D1.1. The manufacturer of the anchor channel shall demonstrate that the manufacturing plant is capable of

performing the selected welding process in accordance with the applicable standards.

1.3.4.2 I-shaped anchors shall comply with the following dimensions: length lA ≥ 13/16 in. (30 mm), web thickness p ≥ 5/32 in. (4 mm), width of anchor head d1 ≥ 9/16 in. (14 mm), width 3/8 in. (10 mm) ≤ wA ≤ 2 in. (51 mm).

1.3.4.3 Round headed anchors shall comply with the following dimensions: length lA ≥ 13/16 in. (30 mm), shaft

diameter d2 ≥ 1/5 in. (5 mm), and head diameter d1 ≥ 1/2 in. (12 mm). The head is forged to the anchor or may consist

of a nut.



1.3.4.4 Round headed anchors that are attached forged or bolted to the channel back shall comply with the

requirements of Section 1.3.4.3 of this annex. The anchors shall be placed into prefabricated holes in the back of the

channel and connected rigidly with the channel back.

1.3.4.5 Deformed reinforcing bars as defined in Section 2.2 of ACI 318-05, -08, -11 and Section 2.3 of ACI 318-14

may be attached to the channel in lieu of anchors.

1.3.4.56 The axial distance between the end of the channel and the nearest anchor, x, shall be ≥ 1 in. (25.4 mm).

1.3.4.67 The axial spacing between anchors, s, shall be at least 2 in. (51 mm). Where deformed reinforcing bars are

used as anchors, the axial spacing between bars, s, shall be at least 4 in. (100 mm). The maximum spacing, s, shall

not be larger than the smaller of 5 times the minimum edge distance cmin and 16 in. (400 mm). If more than two

anchors are connected to the channel back, their spacing shall be constant.

bch = channel width b1 = channel opening hch = channel height ht = height of channel lips t = thickness of the channel lA = anchor length th = thickness of head portion of headed anchor p = web thickness of the anchor d1 = width / head diameter of the anchor d2 = diameter of the anchor ds = diameter of the channel bolt hef = effective embedment depth α < 45° wA = width of I-shaped anchor



a) Cold formed Anchor channel profile with forged I-shaped round anchors

b) Cold formed Anchor channel profile with welded I-shaped round headed anchors c) Anchor channel profile with deformed reinforcing bars

FIGURE 1—EXAMPLES OF ANCHOR CHANNELS WITH CORRESPONDING CHANNEL BOLT

D.5.2.10, Section 17.4.2.10 (ACI 318-14) – Concrete breakout strength of anchor channel in tension

D.5.2.10.1, Section 17.4.2.10.1 (ACI 318-14) – The nominal concrete breakout strength, Ncb, of a single anchor in

tension of an anchor channel shall be determined in accordance with Eq. (D-4.a, ACI 318-05,-08), (D-3.a, ACI 318-

11), (17.4.2.10.1, ACI 318-14).

cb b s N ed N co N c N cp NN N , , , , , (D-4.a, ACI 318-05,-08), (D-3.a, ACI 318-11),

(17.4.2.10.1, ACI 318-14)

Factors ψs,N, ψed,N, ψco,N, ψc,N, and ψcp,N are defined in D.5.2.10.4, D.5.2.10.5, D.5.2.10.6, D.5.2.10.7, and D.5.2.10.8

or Sections 17.4.2.10.4, 17.4.2.10.5, 17.4.2.10.6, 17.4.2.10.7, and 17.4.2.10.8 of ACI 318-14 respectively. Nb is

defined in D.5.2.10.2 or Section 17.4.2.10.2 of ACI 318-14.



Where anchors consist of deformed reinforcing bars in accordance with Sections 1.3.1 and 1.3.4.5 and the minimum

spacing requirement of 1.3.4.7 is met, verification for concrete breakout is not required provided that the deformed

reinforcing bars are lap spliced with reinforcing bars in the member according to the requirements of ACI 318-11

Section 12.14 or ACI 318-14 Section 25.5.

D.5.3.7, Section 17.4.3.7 (ACI 318-14) – Pullout Strength of Anchor Channels in Tension:

D.5.3.7.1, Section 17.4.3.7.1 (ACI 318-14) – For headed anchors of anchor channels, the pullout strength Npn shall

be computed in accordance with D.5.3.1, D.5.3.4, and D.5.3.6 of ACI 318-05, -08, -11, Sections 17.4.3.1, 17.4.3.4,

17.4.3.6 of ACI 318-14.

D.5.4.3, Section 17.4.4.3 (ACI 318-14) – Concrete Side-Face Blowout Strength of Anchor Channels in Tension:

D.5.4.3.1, Section 17.4.4.3.1 (ACI 318-14) – For headed anchors of anchor channels with deep embedment close to

an edge (hef > 2.0 ca1) the nominal side-face blowout strength, Nsb, of a single anchor shall be computed in

accordance with Eq. (D-17a, ACI 318-05,-08), (D-16a, ACI 318-11), (17.4.4.3.1, ACI 318-14).

Item 2: Interaction equations (Section D.7.4.2 and D.7.4.3)

It is proposed to modify the language in the equations for combined tension and shear to mirror that in

ACI 318-14, that is, that the exponent for interaction is unreduced for seismic resistance in all cases. The

current text requires an exponent of 1 for anchor channels in structures assigned to SDC C and above.

However, the research upon which this reduced exponent was based did not include anchor channels,

and the effects noted in that research, namely that the anchor suffers severe surface spalling leading to a

dramatic reduction in tension capacity, is not observed in the cyclic testing of anchor channels.


D.7.4.2.1, Section 17.6.4.2.1 (ACI 318-14) – For anchor and connection between anchor and channel

, , , ,

, , , ,

max ; max ; 1.0 max ;a a a aa a

ua y ua y ua x ua xua ua

sa sc sa y sc y sa x sc x

V V V VN N

N N V V V V

(D-32b, ACI 318-05,-08),

(D-42b, ACI 318-11),

(17.6.4.2.1 ACI 318-14)

where

α = 1 for anchor channels to resist tension and shear loads in SDC C, D, E or F

In all other cases:

α = 2 for anchor channels with max (Vsa,y; Vsc,y) ≤ min (Nsa; Nsc)

α = 1 for anchor channels with max (Vsa,y; Vsc,y) > min (Nsa; Nsc)



It shall be permitted to assume reduced values for Vsa,y and Vsc,y corresponding to the use of an exponent α = 2. In

this case the reduced values for Vsa,y and Vsc,y shall also be used in Section D.6.1.4.1, Section 17.5.1.4.1 (ACI 318-

14) c) and d).

D.7.4.2.2, Section 17.6.4.2.2 (ACI 318-14) – At the point of load application

, ,

, ,

1.0b bb

ua y ua xua

sl sl y sl x

V VN

N V V (D-32c, ACI 318-05,-08), (D-42c, ACI 318-11), (17.6.4. 2.2a ACI 318-14)

,, ,

, , ,

1.0b b

ua yu flex ua x

s flex sl y sl x

VM V

M V V(D-32d, ACI 318-05,-08), (D-42d, ACI 318-11), (17.6.4. 2.2b ACI

318-14)

where


In all other cases:

α = 2 for anchor channels with Vsl,y ≤ Ns,l

α = 1 for anchor channels with Vsl,y > Ns,l

It shall be permitted to assume a reduced value for Vsl,y corresponding to the use of an exponent α = 2. In this case

the reduced value for Vsl,y shall also be used in Section D.6.1.4.1, Section 17.5.1.4.1 (ACI 318-14) b).

D.7.4.3, Section 17.6.4.3 (ACI 318-14) – For concrete failure modes, of anchor channels Eq. (D-32e, ACI 318-05,-

08), (D42e, ACI 318-11), (17.6.4. 3 ACI 318-14) shall be satisfied designed to satisfy the requirements in D.7.4.3.1,

Section 17.6.4.3.1 (ACI 318-14) through D.7.4.3.3, Section 17.6.4.3.3 (ACI 318-14).

, ,

, ,

1.0a aa

ua y ua xua

nc nc y nc x

V VN

N V V

(D-32e, ACI 318-05,-08), (D-42e, ACI 318-11), (17.6.4. 3 ACI 318-14)

Where


In all other cases:

α = 1.5 anchor channels without anchor reinforcement or with anchor reinforcement to take up tension and

shear loads

α = 1.0 anchor channels with anchor reinforcement to take up tension or shear loads



D.7.4.3.1, Section 17.6.4.3.1 (ACI 318-14) – If

, ,

, ,

0.2a a

ua y ua x

nc y nc x

V V

V V, then full strength in tension shall be

permitted: an uaN N

D.7.4.3.2, Section 17.6.4.3.2 (ACI 318-14) – If auaN ≤ 0.2 Nn, then full strength in shear shall be permitted:

, ,

, ,

1.0a a

ua y ua x

nc y nc x

V V

V V

D.7.4.3.3, Section 17.6.4.3.3 (ACI 318-14) – If

, ,

, ,

0.2a a

ua y ua x

nc y nc x

V V

V V and a

uaN > 0.2 Nn, then Eq. (D-32e),

(17.6.4.3 a, ACI 318-14) applies.

, ,

, ,

1.2a aa

ua y ua xua

nc nc y nc x

V VN

N V V (D-32e, ACI 318-05,-08), (D-42e, ACI 318-11), (17.6.4. 3.3a ACI 318-14)

D.7.4.3.4, Section 17.6.4.3.4 (ACI 318-14) – Alternatively, instead of satisfying D.7.4.3.1, Section 17.6.4.3.1 (ACI

318-14) through D.7.4.3.3, Section 17.6.4.3.3 (ACI 318-14), the interaction equation (D-32f, ACI 318-05,-08), (D-42b,

ACI 318-11), (17.6.4.3b, ACI 318-14) may be satisfied

5/3 5/35/3

, ,

, ,

1.0a aa

ua y ua xua

nc nc y nc x

V VN

N V V (D-32f, ACI 318-05,-08), (D-42e, ACI 318-11), (17.6.4. 3.3b ACI 318-14)

Item 3: Minimum spacing in case of anchor channels with I-shaped anchors oriented longitudinally

(Section 1.3.4.7)

It is proposed to add information on the clear spacing between I-shaped anchors which are oriented

longitudinally to permit concrete to flow readily into the spaces between the anchors.


1.3.4.7 The axial spacing between anchors, s, shall be at least 2 in. (51 mm). The maximum spacing, s, shall not be

larger than the smaller of 5 times the minimum edge distance cmin and 16 in. (400 mm). If more than two anchors are

connected to the channel back, their spacing shall be constant. The spacing between I-anchors oriented

longitudinally shall be sufficient to permit concrete to flow readily into the spaces between the anchors. See Section

7.6 of ACI 318-05, -08, -11 and Section 25.2 of ACI 318-14.



The changes proposed above have been developed by the CAMA AC232 task group and are intended to

improve the clarity and efficiency of the assessment requirements for anchor channels. We request that

these changes be submitted to the ES Committee for consideration at the earliest possible opportunity.

We would also agree to use the Alternative Criteria Development Process for these changes.

Thank you for your attention in this regard.

Sincerely,

DAN WALKER, P.E.

www.icc-e

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PROPOSED REVISIONS TO THE ACCEPTANCE CRITERIA FOR ANCHOR CHANNELS IN CONCRETE ELEMENTS (AC232)

Page 7 of 95

1.0 Introduction:

1.1 Purpose:

1.1.1 The purpose of this annex is to establish testing programs and evaluation requirements for recognition of anchor

channels in ICC Evaluation Service, LLC (ICC-ES) evaluation reports under the 2015, 2012, 2009, 2006 International Building

Code® (IBC) and the 2015, 2012, 2009, 2006 International Residential Code® (IRC). Bases of recognition are IBC Section

104.11 and IRC Section R104.11. This acceptance criteria describes the principles and requirements for safety, serviceability

and durability of anchor channels for use in uncracked or cracked concrete.

1.2 Scope:

1.2.1 This annex to AC232 applies to anchor channels used to resist loads in cracked and uncracked normal weight and

lightweight concrete and includes assessment of strength capacity, design procedures and quality control. Special inspection

in accordance with Chapter 17 of the IBC is required. Modifications to the strength design requirements of ACI 318, Appendix

D or ACI 318-14 Chapter 17 as applicable are provided in Section 3.0 of this annex.

1.2.2 The following loading conditions are outside the scope of this acceptance criteria:

1.2.2.1 Fatigue loading.

1.3 Anchor Channels Permitted Under This Acceptance Criteria:

1.3.1 Anchor Channel Assemblies: Anchor channels consist of a channel produced from hot-rolled or cold-formed steel and

at least two metal anchors on the channel web back as illustrated in Figure 1 and Figure 2 of this annex whereby anchors may

consist of round headed anchors, I-shaped anchors, or deformed reinforcing bars. The anchor channels shall be placed flush

with the concrete surface as illustrated in Figure 3 of this annex. A fixture shall be connected to the anchor channel by channel

bolts (hammer head or hooked channel bolts) with nut and washer in accordance with Figure 1 and Figure 3 of this annex.

1.3.2 Loading of Anchor Channels: The anchor channel may be used to transmit tensile loads, shear loads perpendicular

to the longitudinal channel axis, shear loads acting in the direction of the longitudinal channel axis (optional), or any

combination of these loads applied at any location between the outermost anchors of the anchor channel in accordance with

Figure 4 of this annex. Transfer of tension loads takes place via interlock between the channel bolt and the channel lips,

bending of the channel, tension in the anchors, and mechanical interlock with the concrete. Shear loads perpendicular to the

longitudinal channel axis are transferred by the anchors and by compression stresses between the side of the channel and the

concrete. However, for reasons of simplicity, it is assumed that the shear loads are transferred by the anchors only [see

D.3.1.1.3 (ACI 318-05, ACI 318-08), D.3.1.2.3 (ACI 318-11), Section 17.2.1.2.3 (ACI 318-14)]. Shear loads acting in the

direction of the longitudinal channel axis are assumed to be transferred from the channel bolt via the channel and the anchors

into the concrete without consideration of friction and/or adhesion [see D.3.1.1.5 (ACI 318-05, ACI 318-08), D.3.1.2.5 (ACI

318-11), Section 17.2.1.1.5 (ACI 318-14)].

Where recognition is sought for static shear loading along the longitudinal axis of the anchor channel, the longitudinal loads

shall be transferred by a positive load transfer mechanism [e.g. mechanical interlock between the channel bolt and the channel

profile by notches in the smooth channel lips created by notching channel bolts (example see Fig. 5a) or by matching

serrations between the channel lips and channel bolt (example see Fig. 5b)].

Transfer of shear load in the direction of the longitudinal channel axis from the channel bolt via channel and anchors into the

concrete shall use a positive load transfer mechanism that shall be capable to ensure safe and effective behavior under

normal and adverse conditions, both during installation and in service. Factors included are installation conditions in concrete

and torqueing of the channel bolt.

Where recognition is sought for seismic loading in Seismic Design Categories C, D, E and F recognition for shear loads in

direction of the longitudinal channel axis is required.


Page 8 of 95

1.3.3 Channels: The channel height shall be 0.6 in. (15 mm) ≤ hch ≤ 2 in. (51 mm) and the corresponding channel width 1 in.

(25.4 mm) ≤ bch ≤ 3 in. (76 mm). The minimum channel length shall be 4 in. (102 mm). The maximum length is unlimited.

The effective embedment depth of anchor channels, hef, may not exceed 7.1 in. (180 mm) for anchor channels with I-shaped

anchors.

The anchor channel geometry must fulfill the following requirements: hch/hef ≤ 0.5 and bch/hef ≤ 0.7.

1.3.4 Anchors: The headed anchors shall be produced from carbon or stainless steel. Deformed reinforcing bars must

conform to one of the types listed in (a) through (g) below:

(a) ASTM A615 – carbon steel

(b) ASTM A706 – low-alloy steel

(c) ASTM A996- axle steel and rail steel; bars from tail steel shall be Type R

(d) ASTM A955 – stainless steel

(e) ASTM A1035 – low-carbon chromium steel

(f) CAN/CSA-G30.18- billet steel bars for concrete reinforcement

(g) DIN 488- BSt 500- carbon steel

The anchors may be welded, forged or bolted to the channel. Where deformed reinforcing bars are welded, they shall be of a

weldable grade. All anchors attached to the anchor channel shall be of the same type, size and embedment.

1.3.4.1 Anchors that are welded to the channel may consist of I-shaped profiles, or round-headed anchors, or deformed

reinforcing bars. The welding shall be performed by any appropriate welding method in accordance with AWS D1.1. The

manufacturer of the anchor channel shall demonstrate that the manufacturing plant is capable of performing the selected

welding process in accordance with the applicable standards.

1.3.4.2 I-shaped anchors shall comply with the following dimensions: length lA ≥ 13/16 in. (30 mm), web thickness p ≥ 5/32 in.

(4 mm), width of anchor head d1 ≥ 9/16 in. (14 mm), width 3/8 in. (10 mm) ≤ wA ≤ 2 in. (51 mm).

1.3.4.3 Round headed anchors shall comply with the following dimensions: length lA ≥ 13/16 in. (30 mm), shaft diameter d2 ≥ 1/5 in. (5 mm), and head diameter d1 ≥ 1/2 in. (12 mm). The head is forged to the anchor or may consist of a nut.

1.3. 4.4 Round headed anchors that are attachedforged or bolted to the channel back shall comply with the requirements of

Section 1.3.4.3 of this annex. The anchors shall be placed into prefabricated holes in the back of the channel and connected

rigidly with the channel back.

1.3.4.5 Deformed reinforcing bars as defined in Section 2.2 of ACI 318-05, -08, -11, and Section 2.3 of ACI 318-14 may be

attached to the channel in lieu of anchors as described in Section 1.3.4.4 above.

1.3.4.65 The axial distance between the end of the channel and the nearest anchor, x, shall be ≥ 1 in. (25.4 mm).

1.3.4.76 The axial spacing between anchors, s, shall be at least 2 in. (51 mm). Where deformed reinforcing bars are used as

anchors, the axial spacing between bars, s, shall be at least 4 inches (100 mm).The maximum spacing, s, shall not be larger

than the smaller of 5 times the minimum edge distance cmin and 16 in. (400 mm). If more than two anchors are connected to

the channel back, their spacing shall be constant. The spacing between I-anchors oriented longitudinal to the channel axis

shall be sufficient to permit concrete to flow readily into the spaces between the anchors. See Section 7.6 of ACI 318-05, -08, -

11 and Section 25.2 of ACI 318-14.

P

1

e

PROPOSED REV

1.3.5 Durabili

environment, un

VISIONS TO TH

ty: Depending

nder external a

E ACCEPTANC

g on the mater

atmospheric co

E CRITERIA FO

P

rial of channel

onditions, in an

bch = chb1 = chahch = chht = heigt = thicklA = ancth = thicp = webd1 = widd2 = diads = diahef = effα < 45°wA = wid

OR ANCHOR CH

Page 9 of 95

bolt, channel

industrial atmo

hannel width annel openinghannel height ght of channel kness of the chchor length ckness of head b thickness of tdth / head diamameter of the anameter of the chfective embedm

dth of I-shaped

HANNELS IN CO

and anchor ch

osphere, or in a

lips hannel

portion of heathe anchor

meter of the ancnchor hannel bolt ment depth

d anchor

ONCRETE ELEM

hannels may b

a marine enviro

ded anchor

chor

MENTS (AC232)

be used in a d

onment.

dry internal

P

PROPOSED REV

F

VISIONS TO TH

FIGURE 1—EX

E ACCEPTANC

a) C

b) C

c) A

XAMPLES OF A

E CRITERIA FO

P

Cold formed An

Cold formed An

Anchor channe

ANCHOR CHA

OR ANCHOR CH

age 10 of 95

nchor channel p

nchor channel p

l profile with de

ANNELS WITH

HANNELS IN CO

profile with forg

profile with wel

eformed reinfor

H CORRESPON

ONCRETE ELEM

ged roundI-sha

lded I-shaped r

rcing bars

NDING CHANN

MENTS (AC232)

aped anchors

round headed a

NEL BOLT

anchors


Page 28 of 95

Nss = Ase,N · futb (D-3.b, ACI 318-05,-08), (D-2.b, ACI 318-11), (17.4.1.3.4 ACI 318-14)

where Ase,N is the effective cross-sectional area in tension, in2 (mm2); and futb shall be taken as the smaller of 1.9 fyb and

125,000 psi (860 MPa).

D.5.1.3.5, Section 17.4.1.3.5 (ACI 318-14) – The nominal bending strength of the anchor channel, Ms,flex, shall be taken from

the ICC-ES Evaluation Service Report.

D.5.2.10, Section 17.4.2.10 (ACI 318-14) – Concrete breakout strength of anchor channel in tension

For anchor channels where hch/hef ≤ 0.4, the effective embedment depth is determined according to Figure 3a). For anchor

channels where 0.4 < hch/hef ≤ 0.5, the concrete cone resistance may be calculated using one of the following options:

a) the effective embedment depth h*ef is determined according to Figure 3b),with the value for cn,N = 1.0 and scr,N = 3

h*ef, and ccr,N = 1.5 h*ef.

or

b) the effective embedment depth hef is determined in according to Figure 3a), but the value for cn,N shall be taken from

the ICC-ES Evaluation Service Report.

D.5.2.10.1, Section 17.4.2.10.1 (ACI 318-14) – The nominal concrete breakout strength, Ncb, of a single anchor in tension of

an anchor channel shall be determined in accordance with Eq. (D-4.a, ACI 318-05,-08), (D-3.a, ACI 318-11), (17.4.2.10.1, ACI

318-14.

cb b s N ed N co N c N cp NN N , , , , ,

(D-4.a, ACI 318-05,-08), (D-3.a, ACI 318-11), (17.4.2.10.1, ACI 318-14)

Factors ψs,N, ψed,N, ψco,N, ψc,N, and ψcp,N are defined in D.5.2.10.4, D.5.2.10.5, D.5.2.10.6, D.5.2.10.7, and D.5.2.10.8 or

Sections 17.4.2.10.4, 17.4.2.10.5, 17.4.2.10.6, 17.4.2.10.7, and 17.4.2.10.8 of ACI 318-14 respectively. Nb is defined in

D.5.2.10.2 or Section 17.4.2.10.2 of ACI 318-14.

Where anchors consist of deformed reinforcing bars in accordance with Sections 1.3.1 and 1.3.4.5 and the minimum spacing

requirement of Section 1.3.4.7 is met, verification for concrete breakout is not required provided that the deformed reinforcing

bars are lap spliced with reinforcing bars in the member according to the requirements of ACI 318-11 Section 12.14 or ACI

318-14 Section 25.5.

D.5.2.10.2, Section 17.4.2.10.2 (ACI 318-14) – The basic concrete breakout strength of a single anchor in tension in cracked

concrete, Nb, shall be determined in accordance with (D-7a, ACI 318-05,-08), (D-6a, ACI 318-11), (17.4.2.10, ACI 318-14).

' 1.5,24b ch N c efN f h , lbf (D-7a, ACI 318-05,-08), (D-6a, ACI 318-11), (17.4.2.10a, ACI 318-14)

' 1.5,10b ch N c efN f h , N (D-7a, ACI 318-05,-08), (D-6a, ACI 318-11), (17.4.2.10a, ACI 318-14)

where

hch/hef ≤ 0.4, cn,N shall be calculated as:

efch N

h

0.15

, 17.1

, inch-pound unit (D-7b, ACI 318-05,-08), (D-6b, ACI 318-11), (17.4.2.10b, ACI 318-14)

efch N

h

0.15

, 1180

, (SI-units) (D-7b, ACI 318-05,-08), (D-6b, ACI 318-11), (17.4.2.10b, ACI 318-14)


Page 34 of 95

D.5.2.10.9, Section 17.4.2.10.9 (ACI 318-14) – Where anchor reinforcement is developed in accordance with ACI 318-11

Chapter 12 or ACI 318-14 Chapter 25 on both sides of the breakout surface for an anchor of an anchor channel, the design

strength of the anchor reinforcement, Nca, shall be permitted to be used instead of the concrete breakout strength, Ncb, in

determining Nn. The anchor reinforcement for one anchor shall be designed for the tension force, Naua, on this anchor using

a strut-and-tie model. The provisions in Figure RD.5.2.10.9 or Figure 17.4.2.10.9, ACI 318-14 shall be taken into account

when sizing and detailing the anchor reinforcement. Anchor reinforcement shall consist of stirrups made from deformed

reinforcing bars with a maximum diameter of 5/8 in. (No. 5 bar) (16 mm). A strength reduction factor of 0.75 shall be used in

the design of the anchor reinforcement.

For anchor channels located parallel to the edge of a concrete member or in a narrow concrete member, the plane of the

anchor reinforcement shall be arranged perpendicular to the longitudinal axis of the channel (as shown in Figure RD.5.2.10.9,

Figure 17.4.2.10.9, ACI 318-14).

FIGURE RD.5.2.10.9 (FIGURE 17.4.2.10.9, ACI 318-14) —ARRANGEMENT OF ANCHOR REINFORCEMENT

FOR ANCHOR CHANNELS LOADED BY TENSION LOAD

D.5.3.7, Section 17.4.3.7 (ACI 318-14) – Pullout Strength of Anchor Channels in Tension:

D.5.3.7.1, Section 17.4.3.7.1 (ACI 318-14) – For headed anchors of anchor channels, the pullout strength Npn shall be

computed in accordance with D.5.3.1, D.5.3.4, and D.5.3.6 of ACI 318-05, -08, -11, Sections 17.4.3.1, 17.4.3.4, 17.4.3.6 of

ACI 318-14.

D.5.4.3, Section 17.4.4.3 (ACI 318-14) – Concrete Side-Face Blowout Strength of Anchor Channels in Tension:

D.5.4.3.1, Section 17.4.4.3.1 (ACI 318-14) – For headed anchors of anchor channels with deep embedment close to an edge

(hef > 2.0 ca1) the nominal side-face blowout strength, Nsb, of a single anchor shall be computed in accordance with Eq. (D-

17a, ACI 318-05,-08), (D-16a, ACI 318-11), (17.4.4.3.1, ACI 318-14).

sb sb s Nb g Nb co Nb h Nb c NbN N 0, , , , , , lbf (N) (D-17a, ACI 318-05,-08), (D-16a, ACI 318-11), (17.4.4.3.1, ACI 318-14)

ℓd

35º

anchor reinforcement

ℓdh

Nua

surface reinforcement

≤ 0.5hef≤ 0.5hef

ℓd

35º


ℓdh

Nua

surface reinforcement

≤ 0.5hef≤ 0.5hef

ℓd

ℓdh

Nua


≤ 0.5hef≤ 0.5hef

35º

ℓd

ℓdh

Nua


≤ 0.5hef≤ 0.5hef

35º


Page 46 of 95

where buaN and

0.52 2

, ,b b b

ua ua y ua xV V V are the design tension load and design shear load on the channel bolt under

consideration.

This verification is not required in case of shear load with lever arm as Eq. (D-20b, ACI 318-05.-08), (D-29b, ACI 318-11),

(17.5.1.4.1b, ACI 318-14) accounts for the interaction.

D.7.4.2, Section 17.6.4.2 (ACI 318-14) – For steel failure modes of anchor channels Eq. (D-32b, ACI 318-05,-08), (D42b, ACI

318-11), (17.6.4.2.1 ACI 318-14), (D-32c, ACI 318-05,-08), (D42c, ACI 318-11), (17.6.4.2.2a ACI 318-14) and (D-32g, ACI

318-05,-08), (D42g, ACI 318-11), (17.6.4.3.2.2b ACI 318-14) shall be satisfied.

D.7.4.2.1, Section 17.6.4.2.1 (ACI 318-14) – For anchor and connection between anchor and channel

, , , ,

, , , ,

max ; max ; 1.0 max ;a a a aa a

ua y ua y ua x ua xua ua

sa sc sa y sc y sa x sc x

V V V VN N

N N V V V V

(D-32b, ACI 318-05,-08),

(D-42b, ACI 318-11),

(17.6.4.2.1 ACI 318-14)

where


In all other cases:

α = 2 for anchor channels with max (Vsa,y; Vsc,y) ≤ min (Nsa; Nsc)

α = 1 for anchor channels with max (Vsa,y; Vsc,y) > min (Nsa; Nsc)

It shall be permitted to assume reduced values for Vsa,y and Vsc,y corresponding to the use of an exponent α = 2. In this case

the reduced values for Vsa,y and Vsc,y shall also be used in Section D.6.1.4.1, Section 17.5.1.4.1 (ACI 318-14) c) and d).

D.7.4.2.2, Section 17.6.4.2.2 (ACI 318-14) – At the point of load application

, ,

, ,

1.0b bb

ua y ua xua

sl sl y sl x

V VN

N V V (D-32c, ACI 318-05,-08), (D-42c, ACI 318-11), (17.6.4. 2.2a ACI 318-14)

,, ,

, , ,

1.0b b

ua yu flex ua x

s flex sl y sl x

VM V

M V V(D-32d, ACI 318-05,-08), (D-42d, ACI 318-11), (17.6.4. 2.2b ACI 318-14)

where


In all other cases:

α = 2 for anchor channels with Vsl,y ≤ Ns,l

α = 1 for anchor channels with Vsl,y > Ns,l

It shall be permitted to assume a reduced value for Vsl,y corresponding to the use of an exponent α = 2. In this case the

reduced value for Vsl,y shall also be used in Section D.6.1.4.1, Section 17.5.1.4.1 (ACI 318-14) b).

D.7.4.3, Section 17.6.4.3 (ACI 318-14) – For concrete failure modes of anchor channels Eq. (D-32e, ACI 318-05,-08), (D42e,

ACI 318-11), (17.6.4. 3 ACI 318-14) shall be satisfied designed to satisfy the requirements in D.7.4.3.1, Section 17.6.4.3.1

(ACI 318-14) through D.7.4.3.3, Section 17.6.4.3.3 (ACI 318-14).


Page 47 of 95

, ,

, ,

1.0a aa

ua y ua xua

nc nc y nc x

V VN

N V V

(D-32e, ACI 318-05,-08), (D-42e, ACI 318-11), (17.6.4. 3 ACI 318-14)

Where


In all other cases:

α = 1.5 anchor channels without anchor reinforcement or with anchor reinforcement to take up tension and shear loads

α = 1.0 anchor channels with anchor reinforcement to take up tension or shear loads

D.7.4.3.1, Section 17.6.4.3.1 (ACI 318-14) – If

, ,

, ,

0.2a a

ua y ua x

nc y nc x

V V

V V , then the full strength in tension shall be

permitted: an uaN N

D.7.4.3.2, Section 17.6.4.3.2 (ACI 318-14) – If 0.2aua nN N , then the full strength in shear shall be permitted:

, ,

, ,

1.0a a

ua y ua x

nc y nc x

V V

V V

D.7.4.3.3, Section 17.6.4.3.3 (ACI 318-14) – If

, ,

, ,

0.2a a

ua y ua x

nc y nc x

V V

V V and 0.2a

ua nN N ,then Eq. (D-32e),

Eq. ( 17.6.4.3.a ACI 318-14) applies:

, ,

, ,

1.2a aa

ua y ua xua

nc nc y nc x

V VN

N V V (D-32e, ACI 318-05,-08), (D-42e, ACI 318-11), (17.6.4.3.3a ACI 318-14)

D.7.4.3.4, Section 17.6.4.3.4 (ACI 318-14) – Alternatively, instead of satisfying D.7.4.3.1, Section 17.6.4.3.1 (ACI 318-14)

through D.7.4.3.3, Section 17.6.4.3.3 (ACI 318-14), the interaction equation (D-32f, ACI 318-05,-08), (D-42f, ACI 318-11),

(17.6.4.3.3b ACI 318-14) may be satisfied:

5/3 5/35/3

, ,

, ,

1.0a aa

ua y ua xua

nc nc y nc x

V VN

N V V (D-32f, ACI 318-05,-08), (D-42f, ACI 318-11), (17.6.4.3.3b ACI 318-14)

D.8.8, Section 17.7.8 (ACI 318-14) – For anchor channels the following additional provisions apply

D.8.8.1, Section 17.7.8.1 (ACI 318-14) – The minimum edge distance shall be taken from the ICC-ES Evaluation Service

Report.

D.8.8.2, Section 17.7.8.2 (ACI 318-14) – The minimum anchor spacing is 2 inches (50 mm)

D.8.8.3, Section 17.7.8.3 (ACI 318-14) – The critical edge distance, cac, shall be taken as 3hef.

3.2 Allowable Stress Design (ASD) Information (Optional):

TO: PARTIES INTERESTED IN ANCHOR CHANNELS … · anchors connected to the back of the channel. ......

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