Page 281 - Civil Engineering Formulas

BUILDING AND STRUCTURES FORMULAS 215

Upper-story shear, V s

ΣF
A A
d 1
d 2
M 1
M 2

d c

Lower-story shear
FIGURE 9.2 Rigid connection of steel members with webs
in a common plane.

plane AA in Fig. 9.2, exceed F , that is, when
F is larger than d t F , where d c
v
c w
v
is the depth and t is the web thickness of the member resisting
F. The shear
w
may be calculated from

F 0.95d 1 0.95d 2 V s (9.30)
M 2
M 1
where V shear on the section
s
M M M 1G
1
1L
M moment due to the gravity load on the leeward side of the connection
1L
M 1G moment due to the lateral load on the leeward side of the connection
M M M 2G
2
2L
M moment due to the lateral load on the windward side of the
2L
connection
M 2G moment due to the gravity load on the windward side of the
connection
STRESSES IN THIN SHELLS
Results of membrane and bending theories are expressed in terms of unit forces
and unit moments, acting per unit of length over the thickness of the shell. To
compute the unit stresses from these forces and moments, usual practice is to