How to Make a 2D Structure of a Bridge

Draw a horizontal line across the paper to represent the edge of the land and the surface of the water.

Draw a single straight line to represent the deck of the bridge. Draw a second line above the first to represent the width of the material. Color in the space between the lines.

Determine the type of bridge you will draw. There are four main types of bridges: beam, arch, suspension and cantilever. Beam bridges stretch straight across and may or may not have supports. The span of arch bridges is built on top of a series of connected arches. Suspension bridges are characterized by tall towers connected to the span by a series of draped cables. Cantilever bridges use ladder-like components called trusses to span distances but are only anchored at one end.

Sketch rectangles to represent the vertical support beams. Place beams at either end of the bridge and in the water for longer spans. The supports of beam, arch and cantilever bridges are underneath the deck, while the beams of suspension bridges appear to rise from the ground, piercing the deck and continuing up. Color in the rectangles.

Add lines to represent cables for suspension bridges. Use a thick line to represent the main cable that connects the towers and land. Use thin, vertical lines to represent the cables that support the deck.

Make a truss above or below the deck. Draw a horizontal line 2 to 3 inches above the deck. Connect the ends of the line to the deck using straight, vertical lines to form a series of squares. Sketch a diagonal line sloping toward the center of the bridge across each square, dividing it into two triangles.

Sketch the profile of buildings or trees on either side of the bridge to add to the scene and provide scale.

Write notes in the margin concerning the material, design, placement or other bridge-related concerns.