Rebar
![A tied rebar beam cage. This will be embedded inside cast concrete to increase its tensile strength.](/Images/godic/202501/08/Trebar0841.jpg")
![Corroded concrete and rebar at the bridge of Queen Elizabeth Way crossing the Welland River in Niagara Falls, Ontario, Canada.](/Images/godic/202501/08/Qew_bruecke_nf_beton_kaputt_33_von_460841.jpg")
![Rebar inside the Leaning Tower of Nevyansk](/Images/godic/202501/08/Nevjansk_tower_acoustic_room_corner0841.jpg")
![Steel reinforcement bars with color codes indicating the grade](/Images/godic/202501/08/Rebar_and_shingles0841.jpg")
Rebar (short for reinforcing bar), also known as reinforcing steel, reinforcement steel, is a steel bar or mesh of steel wires used as a tension device in reinforced concrete and reinforced masonry structures to strengthen and hold the concrete in tension. Rebar's surface is often patterned to form a better bond with the concrete.