^ Double angle

FIGURE 4.14 Hanger connections.

Prying action in bolts

FIGURE 4.15 Prying action in hanger connections. If LRFD is used:

^req'd where i

Tu = factored tensile force per bolt exclusive of initial tightening and prying force, kip p = length of flange tributary to each bolt measured along the longitudinal axis of the tee or doubleangle section, in.

d = ratio of net area at bolt line to gross area at angle leg or stem face = (p — d ')/p d' = diameter of bolt hole = bolt diameter +1 in.

d[l — (B/Tu — 1)(a'/b')] B = design tensile strength of one bolt = fFtAb (kip) (fFt is given in Table 4.11 and Ab is the nominal area of the bolt) a' = a + d/2 b' = b — d/2

a = distance from bolt centerline to edge of tee flange or angle leg but not more than 1.25 b in. b = distance from bolt centerline to face of tee stem or outstanding leg, in. d = nominal bolt diameter, in.

A design is considered satisfactory if the thickness of the tee flange or angle leg tf exceeds freq>d and B > Tu. Note that if tf is much larger than treq>d, the design will be too conservative. In this case a' should be recomputed using the equation

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