Civil Engineering Reference
In-Depth Information
Figure 3.7
Variation of bending rigidity with moment
differential bending rotation d
is expressed for a differential length
dx
as
M
EI
d
x
d
=
(3.47)
The deflections and rotations of a member can be calculated from Equation (3.47) by
integration if the moment diagram is given analytically. Other forms of integration, such
as moment area method, elastic load method and conjugate beam method are available in
textbooks on structural analysis.
In design practice, the deflections and rotations of a prismatic member are calculated from
formulas available in handbooks and textbooks. A method of organizing the various formulas
is given in the 1983 ACI Commentary 9.5.2.4 (ACI Committee 318, 1983) and in the ACI
Special Publication SP-43 (ACI Committee 435, 1974). In this method the deflection
of a
