Abstract: Two types of free‐standing stairs, each having an axis that makes a 180° turn in plan, are considered. In the first, the horizontal projection of the axis consists of a central semicircle and two equal straight parts, and ...

Abstract: The full, 12×12, stiffness matrix of a free‐standing helicoidal stair is constructed in terms of its geometric characteristics. Knowledge of this stiffness matrix allows incorporation of the stair as a single element into ...