Question
When designing RC and Steel beams, where does the analysis take the member forces?
Answer
In the case of RC beams, sectional design is performed, while for Steel beams, the most unfavorable values are taken from 5 specific locations for design.
Sectional design means that, given the length of the member as L, the member forces at points 0, L/4, L/4 to 3L/4, 3L/4, and L are examined and the values at i, mid, and j are calculated, respectively.
The i-th segment's design value is determined from the unfavorable of the values at 0 and L/4 points, the j-th segment's value is based on the unfavorable values at 3L/4 and L points, and the mid section's value is derived from the unfavorable values within the range of L/4 to 3L/4.
For Steel beams, the design approach is different. Instead of sectional design, the forces are evaluated at 5 specific locations: 0, L/4, L/2, 3L/4, and L. The most unfavorable value among these locations is then chosen for design.
[Image] Beam Diagram
[Image] Design Member Forces Table for RC Beams