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ESR-3699 Page 5 of 18
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<br />4.1.8.3 Seismic Shear: The nominal concrete breakout strength and pryout strength for anchors in shear
<br />must be calculated according to ACI 318-19 17.7.2 and 17.7.3, ACI 318-14 17.5.2 and 17.5.3 or ACI 318-11
<br />D.6.2 and D.6.3, respectively, as applicable, as described in Sections 4.1.6 and 4.1.7 of this report. In
<br />accordance with ACI 318-19 17.7.1.2, ACI 318-14 17.5.1.2 or ACI 318-11 D.6.1.2, as applicable, the value for
<br />nominal steel strength in shear for seismic loads, Vsa,eq, or Vsa,deck, given in Tables 3 or 5 of this report, must
<br />be used in lieu of Vsa, as applicable.
<br />4.1.9 Requirements for Interaction of Tensile and Shear Forces: For designs that include combined
<br />tension and shear, the interaction of tension and shear loads must be calculated in accordance with ACI 318-
<br />19 17.8, ACI 318-14 17.6 or ACI 318-11 D.7, as applicable. For the Sammys anchors, influence of bending on
<br />tension values when loaded in shear must be considered.
<br />4.1.10 Requirements for Critical Edge Distance: In applications where c < cac and supplemental
<br />reinforcement to control splitting of the concrete is not present, the concrete breakout strength in tension for
<br />uncracked concrete, calculated in accordance with ACI 318-19 17.6.2, ACI 318-14 17.4.2 or ACI 318-11 D.5.2,
<br />as applicable, must be further multiplied by the factor ψcp,N given by Eq-3:
<br />𝛹𝑐𝑝,𝑁=𝑐
<br />𝑐𝑎𝑐
<br /> (Eq-3)
<br />whereby the factor 𝛹𝑐𝑝,𝑁 need not be taken as less than 1.5ℎ𝑒𝑓
<br />𝑐𝑎𝑐
<br />. For all other cases, 𝛹𝑐𝑝,𝑁=1.0. In lieu of ACI
<br />318-19 17.9.5, ACI 318-14 17.7.6 or ACI 318-11 D.8.6, as applicable, the values for the critical edge distance,
<br />cac, must be taken from Table 1.
<br />4.1.11 Requirements for Minimum Member Thickness, Minimum Anchor Spacing and Minimum Edge
<br />Distance: In lieu of ACI 318-19 17.9.2, ACI 318-14 17.7.1 and 17.7.3 or ACI 318-11 D.8.1 and D.8.3,
<br />respectively, as applicable, values of smin and cmin as given in Table 1 of this report must be used. In lieu of ACI
<br />318-19 17.9.4, ACI 318-14 17.7.5 or ACI 318-11 D.8.5, minimum concrete thickness hmin as given in Table 1
<br />of this report must be used.
<br />For 1/2-inch-diameter (12.7 mm) Tapcon+ Screw Anchors installed in the soffit of sand-lightweight or
<br />normalweight concrete on steel deck floor and roof assemblies, the anchors must be installed in accordance
<br />with Figure 6 and must have an axial spacing along the flute equal to the greater of 3hef or 1.5 times the flute
<br />width.
<br />4.1.12 Lightweight Concrete: For the use of anchors in lightweight concrete, the modification factor λa equal
<br />to 0.8λ is applied to all values of cf affecting Nn and Vn.
<br />For ACI 318-19 (2021 IBC), ACI 318-14 (2018 and 2015 IBC) and ACI 318-11 (2012 IBC), λ shall be
<br />determined in accordance with the corresponding version of ACI 318.
<br />For anchors installed in the soffit of sand-lightweight concrete-filled steel deck and floor and roof assemblies,
<br />further reduction of the pullout values provided in this report is not required.
<br />4.2 Allowable Stress Design:
<br />4.2.1 General: Design values for use with allowable stress design (working stress design) load combinations
<br />calculated in accordance with Section 1605.1 of the 2021 IBC or Section 1605.3 of the 2018, 2015 and 2012
<br />IBC, must be established as follows:
<br />
<br />=n
<br />ASDallowable,
<br />NT (Eq-4)
<br />
<br />=n
<br />ASDallowable,
<br />VV
<br /> (Eq-5)
<br />
<br />where:
<br />Tallowable, ASD = Allowable tension load (lbf or kN).
<br />Vallowable, ASD = Allowable tension load (lbf or kN).
<br />Nn = Lowest design strength of an anchor or anchor group in tension as determined in
<br />accordance with ACI 318 (-19 and -14) Chapter 17 and 2021, 2018 and 2015 IBC
<br />Section 1905.1.8, ACI 318-11 Appendix D, and Section 4.1 of this report, as
<br />applicable (lbf or kN). For the 2012 IBC, Section 1905.1.9 must be omitted.
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