The concrete arch is curved in which direction?

• A. Curves in One Direction Only
• B. Curves in Two Directions
• C. Circular Symmetry
• D. Not Curved at All

Answer: (A)

The key idea is that a concrete arch is a curved member whose bend occurs in a single plane. When you look at an arch, you see a smooth curve spanning from one support to the other, like an arc. The thickness or depth of the arch is essentially straight, so there isn’t curvature in that orthogonal direction. That’s why it curves in one direction.

If a structure curved in two directions, you’d be dealing with a surface that bends across both axes, like a dome or barrel vault with curvature in multiple directions. Circular symmetry would mean the shape is curved equally in all directions around a central axis, which isn’t the case for a typical arch. Not curved at all would describe a straight beam, not an arch.

So the correct understanding is that the concrete arch curves in one direction.