AC R1 #1. Mr. Vincent Chui Senior Staff Engineer ICC Evaluation Services, Inc Saturn Street, Suite 100 Brea, California 92821

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1 AC R1 #1

2 AC R1 #1 Reference Response to ICC-ES staff letter (AC232) dated August 22, 2016 Department BU Anchors Regulations and Approvals T F E mail philipp.grosser@hilti.com D September 12, 2016 Mr. Vincent Chui Senior Staff Engineer ICC Evaluation Services, Inc Saturn Street, Suite 100 Brea, California Re: Response to ICC-ES staff letter (AC232) dated August 22, 2016 REFERENCE: 1. Staff letter dated August 22, 2016 regarding proposed revisions to the Acceptance Criteria for Anchor Channels in Concrete Elements (AC232) 2. Letter from CAMA to ICC-ES dated June 14, 2016 regarding proposed revisions to the Acceptance Criteria for Anchor Channels in Concrete Elements (AC232) Dear Vincent, I am writing in response to the above-referenced ICC-ES staff letter regarding the CAMA-proposed modifications to AC232. I note that the staff letter contains changes to the text proposed in the CAMA letter of June 14, Besides editorial errors in the draft version of AC232 (compare original language provided in the CAMA letter) which need to be corrected, there are two modifications which are not acceptable. No reasoning is provided by ICC-ES in their letter dated August 22, 2016 for these changes. 1. ICC-ES added to Section that only one value N ss,seis shall be reported for each channel bolt diameter and material and to Section that only one value V ss,seis shall be reported for each channel bolt diameter and material. There is no need for such a conservative requirement. This addition to the criteria would limit the capacity of the channel bolts without technical reason and directly influences existing ESRs. 2. The following proposed language to Section and Section was not accepted by ICC-ES All anchor channel systems shall fulfil the requirements of this section. I believe that this sentence is needed to understand the test requirements for channel bolts and anchor channels. 1

3 In summary, I propose to retain the paragraph structure and language provided in the CAMA letter dated June 14, If you have any questions regarding the above, please do not hesitate to contact me directly. Best regards, Dr. Philipp Grosser cc : J. Silva 2

4 AC R1 #1 IEA GMBH & CO. KG HAUPTSTRAßE STUTTGART IEA GMBH & CO. KG HAUPTSTRAßE 4 D STUTTGART ICC-Evaluation Service Inc. Attn.: Howard Silverman Senior Staff Engineer 3060 Saturn Street, Suite 100 Brea, Ca TELEFON TELEFAX INTERNET: INFO@I-EA.DE VALID FOR ACTIVITIES ACCORDING TO THE SCOPE OF ACCREDITATION. Stuttgart, Sept. 12, 2016 Proposed Revision to AC232, Section of Annex A Your letter dated August 22, 2016 Dear Howard, In the last line of Section the terms Vsa,seis,y, Vsl,seis,y, and Vsc,seis,y should be modified as follows to agree with whereby the determination of Vsa,seis,y, Vsa, y,seis, Vsl,seis,y, Vsl,y,seis and Vsc,seis,y Vsc,y,seis, shall be in accordance with Sincerely yours Prof. R. Eligehausen Dr.-Ing. K. Schmid GESCHÄFTSFÜHRER: SITZ DER GESELLSCHAFT: IEA GMBH & CO. KG BANKVERBINDUNG: STUTTGARTER VOLKSBANK AG PROF. DR. -ING. ROLF ELIGEHAUSEN STUTTGART, HAUPTSTR. 4 KONTO-NR.: DR. -ING. JÖRG ASMUS AMTSGERICHT STUTTGART: HRA BANKLEITZAHL: PROF. DR. -ING. JAN HOFMANN UST-ID.NR.: DE IBAN: DE KOMPLEMENTÄR SWIFT/BIC CODE: VOBADESS IEA INGENIEURBÜRO ELIGEHAUSEN UND ASMUS GMBH

5 IEA GMBH & CO. KG HAUPTSTRAßE 4 D STUTTGART ICC-Evaluation Service Inc. Attn.: Howard Silverman Senior Staff Engineer 3060 Saturn Street, Suite 100 Brea, Ca AC R1 #1 IEA GMBH & CO. KG HAUPTSTRAßE STUTTGART TELEFON TELEFAX INTERNET: INFO@I-EA.DE GÜLTIG FÜR DIE IN DER URKUNDEN- ANLAGE AUFGEFÜHRTEN TÄTIGKEITEN. Stuttgart, September 12, 2016 Proposed Revision to AC232, Sections and (simulated seismic tests under longitudinal shear loads) of Annex A Your letter dated August 22, 2016 Dear Howard, we propose the following changes to Sections and (simulated seismic tests under longitudinal shear loads): 1. Section : Do not change the definition of V s given in AC232, version June Write: V s = minimum value of the mean failure load V ref in acccordance with Eq. (7.13) and V ss in accordance with Eq. (7.14); lbf (N) V ss = 0.7 A ss,v f ut,test ; lbf (N) Eq. (7.14) Note, that the text deleted in the version August 2016 is underlined. 2. Section : Add the following subsections after Section Subsections to are equivalent to to Subsection is new. GESCHÄFTSFÜHRER: SITZ DER GESELLSCHAFT: IEA GMBH & CO. KG BANKVERBINDUNG: STUTTGARTER VOLKSBANK AG PROF. DR. -ING. ROLF ELIGEHAUSEN STUTTGART, HAUPTSTR. 4 KONTO-NR.: DR. -ING. JÖRG ASMUS AMTSGERICHT STUTTGART: HRA BANKLEITZAHL: PROF. DR. -ING. JAN HOFMANN UST-ID.NR.: DE IBAN: DE KOMPLEMENTÄR SWIFT/BIC CODE: VOBADESS IEA INGENIEURBÜRO ELIGEHAUSEN UND ASMUS GMBH

6 2/ If the channel bolt is decisive (V ss is used to calculate V eq according to Eq. (7.12)), the reduction factor α seis,v,x shall be applied only to the specific combination of anchor channel and channel bolt tested If larger channel bolts than tested in Section shall be recognized for seismic loading, test the smallest channel bolt size that results in failure of the anchor channel. All anchor channel systems shall fulfil the requirements of this section. Apply α seis,v,x in accordance with In this case the factor α seis,v,x may also be applied to the combination of anchor channel and channel bolt where the channel bolt was decisive whereby the determination of V sa,x,seis, V sc,x,seis and V sl,x,seis shall be in accordance with Only one set of values V sa,x,seis, V sc,x,seis and V sl,x,seis shall be reported for each channel profile and material Only one value V ss,seis shall be reported for each channel bolt diameter and material. If different values V ss,seis are evaluated in 8.17 and 8.19, the smaller value shall be reported Add an equation to calculate V ss,seis V ss,seis = α V,seis,x V ss Reason: According to the text given in AC232, version August 2016, the shear load to be applied in the direction of the longitudinal channel axis in the simulated seismic shear tests for longitudinal shear depends on the strength of the anchor channel only. It is assumed, that in all cases the shear strength of the channel bolt is higher than the shear strength of the anchor channel in direction of the longitudinal channel axis. However, a manufacturer might specify a channel bolt that has a lower shear strength than the anchor channel. Currently, this case is not covered. Therefore it is proposed not to change the definition of V s in Section ; add the text of to in as subsections to and define in how to

7 3/3 calculate V ss,seis. Because the values V ss,seis evaluated in 8.17 and 8.19 may be different, it is stated in that the smaller value V ss,seis evaluated in 8.17 and 8.19 must be reported as V ss,seis. Note, that the approach proposed for the simulated seismic shear tests with shear loads applied in the direction of the longitudinal channel axis is the same as it is used for simulated seismic shear tests with shear loads applied perpendicular to the direction of the longitudinal channel axis Prof. Dr. R. Eligehausen Dr.-Ing. J. Asmus Dr.-Ing. K. Schmid

8 AC R1 #1 IEA GMBH & CO. KG HAUPTSTRAßE STUTTGART IEA GMBH & CO. KG HAUPTSTRAßE 4 D STUTTGART ICC-Evaluation Service Inc. Attn.: Howard Silverman Senior Staff Engineer 3060 Saturn Street, Suite 100 Brea, Ca TELEFON TELEFAX INTERNET: INFO@I-EA.DE VALID FOR ACTIVITIES ACCORDING TO THE SCOPE OF ACCREDITATION. Stuttgart, Sept. 12, 2016 Proposed Revision to AC232, Sections 2.2 and 3.1 (D ) of Annex A Your letter dated August 22, 2016 Dear Howard, The company Halfen has proposed to change the definition of the distance between channel bolts, s chb, from clear distance to center distance, because the use of the center distance is more appropriate in design. For justifying the proposal the reduction factors for the channel lip strength N sl of a channel (b ch = 52,5mm) and 2 channel bolts with a center spacing of s = 100mm are calculated for bolts with a width of the head b chb,h, ranging between 10mm and 20mm. The ratios of the reduction factors calculated with the center distance (as proposed) to the value valid when using the clear distance (as until now) vary between 1.09 (b chb,h = 10mm) to 1.11 (b chb,h = 20mm). Currently, the center distance between channel bolts is not limited. Therefore it is allowed to place two channel bolts directly beside each other. In this case the reduction factor calculated using the center distance are between 10% (b chb,h = 10mm) to 20% (b chb,h = 20mm) higher than the values valid for the current approach (use of center distance). The authors agree with the proposal to change the definition of the distance between channel bolts to center distance (the term axial distance would be more in line with other definitions given in AC232). However, to the knowledge of the authors no tests have been formed to evaluate the channel lip strength of anchor channels with two channel bolts with a small spacing (e.g. directly beside each other) in comparison to the lip strength valid for one channel bolt. Therefor according to the opinion of the authors the allowable center distance between channel bolts should be limited. In current European Technical Approvals for anchor GESCHÄFTSFÜHRER: SITZ DER GESELLSCHAFT: IEA GMBH & CO. KG BANKVERBINDUNG: STUTTGARTER VOLKSBANK AG PROF. DR. -ING. ROLF ELIGEHAUSEN STUTTGART, HAUPTSTR. 4 KONTO-NR.: DR. -ING. JÖRG ASMUS AMTSGERICHT STUTTGART: HRA BANKLEITZAHL: PROF. DR. -ING. JAN HOFMANN UST-ID.NR.: DE IBAN: DE KOMPLEMENTÄR SWIFT/BIC CODE: VOBADESS IEA INGENIEURBÜRO ELIGEHAUSEN UND ASMUS GMBH

9 2/2 channels a value s chb,min = 5d s is given. A value s chb,min = 3d s might also give sufficiently conservative results. It is proposed to add a new section in Appendix A: The axial spacing between channel bolts shall be not smaller than 3-times the bolt diameter, d s. Alternatively, tests should be performed with typical anchor channels and channel bolts placed directly beside each other to demonstrate, that the proposed modification is sufficiently accurate. Sincerely yours Prof. R. Eligehausen Dr.-Ing. K. Schmid