SHEAR STRENGTH DESIGN FOR BRIDGES

Based on the American Association of State Highway and Transportation Officials (AASHTO) specifications for load-factor design (LFD), the shear capacity, kip (kN), may be computed from

for flexural members with unstiffened webs with h/ t _w < 150 or for girders with stiffened webs but a/ h exceeding 3 or 67,600 (h/ t _w ) ²:

For girders with transverse stiffeners and a/ h less than 3 and 67,600 (h/ t _w ) ², the shear capacity is given by

Stiffeners are required when the shear exceeds V _u.

Chap. 9, Building and Structures Formulas, for symbols used in the preceding equations.

ALLOWABLE-STRESS DESIGN FOR BRIDGE COLUMNS

In the AASHTO bridge-design specifications, allowable stresses in concentrically loaded columns are determined from the following equations:

When Kl/ r is less than C _c,

When Kl/ r is equal to or greater than C _c,

See Table 10.1.

LOAD-AND-RESISTANCE FACTOR DESIGN FOR BRIDGE COLUMNS

Compression members designed by LFD should...