Ribbed steel bars inserted in

concrete to strengthen the concrete.

A structural framework

of wood or metal, arranged in triangles, most commonly used to support a roof or bridge.

The supporting portion of a structure below the first floor construction, or below grade, including the footings.

A mixture of cement, sand, gravel, and water, commonly reinforced with rebar or wire screening.

Force that pulls two things apart.

The gray powder that is the "glue" in concrete.

A pair of gears which convert rotational motion into linear motion.

A vertical structural compression member which supports loads

A masonry support that touches and directly receives thrust or pressure of an arch or bridge.

The front of a structure.

Force that presses things closer together.