The upper deck of a football stadium is supported by braces, each of which transfers a load P = 160 kips to the base of a column (see figure part a). A cap plate at the bottom of the brace distributes the load P to four flange plates (tf = 1 in.) through a pin (dp = 2 in.) to two gusset plates (tg = 1.5 in.) (see figure parts b and c).
Determine the following quantities.
(a) The average shear stress taver in the pin.
(b) The average bearing stress between the flange plates and the pin (sbf), and also between the gusset plates and the pin (sbg).
Disregard friction between the plates.
P P. (a) Stadium brace O Barry Goodno Roof structure Truss member, End P plates Pin . t= 14 mm Gusset. plate 26 mm Truss members supporting a roof Vince Streano/Getty Images Cap plate Flange plate (t=1 in.) Pin (d, = 2 in.) Gusset plate ( = 1.5 in.) (b) Detail at bottom of brace O Barry Goodno P= 160 k Cap plate - Pin (d, = 2 in.) - Flange plate (t= 1 in.) Gusset plate (t= 1.5 in.) P/2 P/2 (c) Section through bottom of brace
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