512 Edge Distance Of Fastners

Minimum distances from centers of fasteners to any edges are given in Tables 5.7 and 5.8.

The AISC specifications for structural steel for buildings have the following provisions for minimum edge distance: The distance from the center of a standard hole to an edge of a connected part should not be less than the applicable value from Table 5.7 nor the value from the equation

where Le = the distance from the center of a standard hole to the edge of the connected part, in

P = force transmitted by one fastener to the critical connected part, kips Fu = specified minimum tensile strength of the critical connected part, ksi t = thickness of the critical connected part, in

Also, Le should not be less than 11/zd when Fp = 1. 2Fu, where d is the diameter of the bolt (in) and Fp is the allowable bearing stress of the critical connected part (ksi).

The AASHTO specifications for highway bridges require the minimum distance from the center of any bolt in a standard hole to a sheared or flame-cut edge to be as shown in Table 5.8. When there is only a single transverse fastener in the direction of the line of force in a standard or short slotted hole, the distance from the center of the hole to the edge connected part (ASD specifications) should not be less than 11/zd when

Pitch Distance
FIGURE 5.9 Maximum pitch of bolts for sealing. (a) Single line of bolts. (b) Double line of bolts.

where Fu = specified minimum tensile strength of conection material, ksi

Le = clear distance between holes or between hole and edge of material in direction of applied force, in d = nominal bolt diameter, in

The AREMA Manual requirement for minimum edge distance for a sheared edge is given in Table 5.8. The distance between the center of the nearest bolt and the end of the connected part toward which the pressure of the bolt is directed should be not less than 2dfp/Fu, where

TABLE 5.7 Minimum Edge Distances (in) for Fastener Holes in Steel for Buildings

At rolled edges of Fastener At sheared plates, shapes, or bars diameter, in edges or gas-cut edges*

5/s

78 11/8

3/4 78

3/4

11/4

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