ESR-2408 - ASC Steel Deck, A Division of ASC Profiles Inc. - ladbs

ESR-2408 | Most Widely Accepted and Trusted Page 33 of 42CONCRETE TYPE 7f’ c = 3,000 PSITABLE 11—ALLOWABLE DIAPHRAGM SHEARS FOR TYPES B, BF, BR, N, NF, NR2W, 2WF, 3W AND 3WF DECKS WITH CONCRETE FILL AND SHEAR STUDS 1-9 (plf)CONCRETESPACING OF SHEAR STUDS 9THICKNESS 8 16” 18” 24” 32”NW 2 – 2 1 / 2” 4,730 4,530 3,400 2,550LW 2 – 2 1 / 2” 4,350 3,860 2,900 2,180LW 3 – 3 1 / 4” 4,350 3,860 2,900 2,180For SI: 1 inch = 25.4 mm, 1 foot = 304.8 mm, 1 plf = 14.594 N/m, 1 pcf =16.018 kg/m 3 , 1 psf = 47.88 Pa, 1 psi = 6894 Pa,1 lbf = 4.45 N, 1 kip = 4.45 kN.1 Values must not exceed 1990 plf for 2 1 / 2 inch normal-weight concrete slabs, 1,900 plf for 2 1 / 2 inch structural lightweight concreteslabs, and 2,200 plf for 3 1 / 4 inch structural lightweight concrete slabs, unless mesh having an area of 0.0025 times the gross area ofconcrete is used. Six by six – W4 x W4 meets this requirement for 2 1 / 2 inch slabs and 4 x 4 – W4 x W4 qualifies for 3 1 / 4 inch slabs.2 Stud diameter must not exceed 2.5 times the thickness of the steel support, unless stud is located directly over support web.3 See Figures 1 and 7 for qualifying deck types and weld patterns.4 For local shear transfer within the field of the diaphragm, 1 / 2 inch-diameter studs having shear values of 6.8 kips per stud fornormal-weight concrete fills and 5.8 kips per stud for lightweight concrete, except as noted hereafter, shall be used. For Deck TypesB-36 and BF-36, where the width of concrete at the stud is less than 2.25 inches, values of 5.7 kips and 4.9 kips, respectively, mustbe used. For Deck Types N-24 and NF-24, where the width of concrete at the stud is less than 4.5 inches, 3 / 4 inch –diameter studswith values of 3.5 kips and 3.0 kips, respectively, must be used.5See Table 19 for Diaphragm Flexibility Limitations.6 Standing seam sidelaps of decks must be fastened by button punches at 36 inches on center. Nestable seams must be fastenedusing either No. 12 self-tapping screws or 1 1 / 2 inch–long fillet welds at 36 inches on center.7 NW = Normal weight (145 pcf). LW = structural lightweight (110 pcf).8 Concrete thickness, t f, is measured from top flute of metal deck.9 Deck Types B-36, BF-36, BR-35, 2W36 and 2WF36, identified in Figure 1, require 1 / 2 inch –diameter studs minimum. Five-eighthsinch-diameterstuds minimum are required for Deck Types NR-24, 3W36 and 3WF36. For Deck Type N-24 and NF-24, 3 / 8-inchdiameterstuds minimum are required and the tabulated shears must be reduced by a factor of 0.74.SHEAR STUDS AT SUPPORTSPERPENDICULAR TO FLUTESSHEAR STUDS AT SUPPORTSPARALLEL TO FLUTESTYPICAL EXTERIOR OR INTERIORSHEAR TRANSFER STUDSFIGURE 7—SHEAR STUD DETAILS