A: Poured concrete walls are actually structural beams. To help you visualize this, think about the horizontal steel I-beams you see as a skyscraper is being built.

Beam bridges, the simplest and most cost-effective kind of span, consist of beams made of wood, iron, or steel -- the stiffer, the better -- laid horizontally atop evenly spaced supports called piers.

Prestressed concrete (see sidebar at right) is an ideal material for beam bridge construction. The concrete withstands the forces of compression well, and the steel rods embedded within resist the ...

The existing Mile Long Bridge, built in 1958, is a mix of concrete and steel beams. The rebuilt bridge will also have a mix, with 600 beams altogether, Kovacs said.

On both sides, concrete pillars with a 1.2m x 2.5m section support a 0.6m wide and 2.2m high beam, whose main core is steel in H section wrapped in reinforced concrete.

The company making them, High Steel Structures, has been building bridge beams since 1951. Inside a cavernous steel fabrication shop in Lancaster, the new beams for the I-81 interchange are being ...

Reinforced with steel cable, the 71-foot spread box beams are 4 feet wide and weigh 27 tons each. Placed six abreast, when combined end to end, the dozen beams will comprise the basis for the 140 ...

ROARING SPRING, Pa. — PennStress, in Blair County, is making 21 concrete beams that will change the Fern Hollow Bridge from a steel K-bridge before it fell earlier this year into a concrete bridge.

Substructure The green shows the extra area, volume and cost of bored pad foundations caused by the extra weight.We assumed a gravel base with a permissible stress of 500 KN/m². Structure The red is ...