DETERMINATE PLANE FRAMES
A frame is composed of several connected members that are either fixed or pin connected at
their ends. The design of these structures often requires drawing the shear and moment
diagrams for each of the members.
A frame is considered to be statically determinate if the bending moments, shears, and axial
forces in all its members, as well as all the external reactions, can be determined by using the
equations of equilibrium and condition.
To analyze any problem, we can use the procedure for analysis outlined in beams. This requires
first determining the reactions at the frame supports. Then, using the method of sections, we
find the axial force, shear force, and moment acting at the ends of each member.
Provided all loadings are resolved into components acting parallel and perpendicular to the
member’s axis, the shear and moment diagrams for each member can then be drawn as
described previously.
SAMPLE PROBLEM #1
Draw the shear and moment diagrams for each of the three members of the frame. Assume the
frame is pin connected at A, C, and D and there is a fixed joint at B.
SAMPLE PROBLEM #2
Draw the shear and moment diagrams for each member of the frame. Assume A is a rocker,
and D is pinned.
SAMPLE PROBLEM #3
Draw the shear and moment diagrams for each member of the frame.The members are pin
connected at A, B, and C.
SAMPLE PROBLEM #4
Draw the shear, bending moment, and axial force diagrams for the frame shown.
ASSIGNMENT:
1) Draw the shear and moment diagrams for each member of the frame. Assume A is fixed, the
joint at B is a pin, and support C is a roller.
2) Draw the shear and moment diagrams for each member of the frame.