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                                                    CRITERIA FOR BUILDING DESIGN


                                                                              CRITERIA FOR BUILDING DESIGN  5.47

                                  TABLE 5.11 Nominal Hole Dimensions, mm
                                                 Standard hole  Oversized hole   Short-slot       Long-slot
                                  Bolt diameter   diameter       diameter      (width × length)  (width × length)
                                     M16            18             20            18 × 22           18 × 40
                                     M20            22             24            22 × 26           22 × 50
                                     M22            24             28            24 × 30           24 × 55
                                     M24            27*            30            27 × 32           27 × 60
                                     M27            30             35            30 × 37           30 × 67
                                     M30            33             38            33 × 40           33 × 75
                                    ≥M36            d + 3         d + 8       (d + 3) × (d + 10)  (d + 3) × 2.5d
                                    *Clearance provided allows the use of a 1-in bolt if desirable.
                                    Note:  d is nominal bolt diameter, mm.
                                    Source:  “Specification for Structural Steel Buildings,” American Institute of Steel Construction, Chicago, Ill., 2005,
                                  with permission.


                                  direction of loading in slip-critical connections, but must be normal to the direction of load in bear-
                                  ing-type connections. Where long-slotted holes are used in an outer ply, plate washers, or a contin-
                                  uous bar with standard holes, having a size sufficient to completely cover the slot after installation,
                                  should be provided. In high-strength bolted connections, the plate washers or continuous bars must
                                          5
                                  be at least  / 16 in (8 mm) thick and of structural-grade material, but generally need not be hardened
                                  (see Art. 5.9.5 for exceptions). Where hardened washers are required, they must be placed over the
                                  outer surface of the plate washer or bar.

                      5.9.7  Spacing and Edge Distance in Bolted Connections
                                                                                                         2
                                  The distance between centers of standard, oversized, or slotted holes should not be less than 2 / 3
                                  times the nominal diameter, d, of the fastener, and preferably should not be less than 3d.
                                    The distance in any direction from the center of a standard hole to an edge of a connected part
                                  should not be less than either the value from either Tables 5.12 or 5.13, or as required for strength (see
                                  Art. 5.9.8). The distance from the center of an oversized or slotted hole to an edge of a connected


                                                                                             †
                                            TABLE 5.12  Minimum Edge Distance,* in, from Center of Standard Hole to
                                            Edge of Connected Part
                                                                           At rolled edges of plates, shapes
                                            Bolt diameter (in)  At sheared edges  or bars, or thermal-cut edges ‡
                                                   1            7                   3
                                                   / 2          / 8                  / 4
                                                   5            1                   7
                                                   / 8         1 / 8                 / 8
                                                   3            1                   1
                                                   / 4         1 / 4
                                                   7            1 §                 1
                                                   / 8         1 / 2                1 / 8
                                                                3 §
                                                  1            1 / 4                1 / 4
                                                                                    1
                                                   1           2                    1
                                                  1 / 8                             1 / 2
                                                   1            1                   5
                                                  1 / 4        2 / 4                1 / 8
                                                   1           1 / 4 × d            1 / 4 × d
                                                                                    1
                                                                3
                                              Over 1 / 4
                                              *Lesser edge distances are permitted if bearing strength requirements, Art. 5.9.8 as appro-
                                            priate, are satisfied.
                                              †For oversized or slotted holes, see Table 5.14.
                                                                           1
                                              ‡All edge distances in this column may be reduced  / 8 in when the hole is at a point where
                                            the required strength does not exceed 25% of the maximum strength in the element.
                                                        1
                                              §These may be 1 / 4 in at the ends of beam connection angles and shear end plates.
                                              Note:  d is nominal bolt diameter, in.
                                              Source: “Specification for Structural Steel Buildings,”  American Institute of Steel
                                            Construction, Chicago, Ill., 2005, with permission.
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