Nonlinear finite elements/Homework 6/Solutions/Problem 1/Part 6

Problem 1: Part 6
What are the major assumptions in the Timoshenko beam formulation described in the book chapter (the authors call these the modified Mindlin-Reissner assumptions)?

The assumptions are:
 * 1) The fibers (or directors) remain straight.
 * 2) The transverse normal stress is negligible (this is also called the plane stress condition.)
 * 3) The fibers are inextensible.