noun
main reinforcement; main rebar
Technical term in reinforced-concrete construction; refers to the primary reinforcing bars that bear tensile stress.
梁の主筋は太い鉄筋を使います。
Thick rebars are used for the main reinforcement of the beam.
主筋の間隔は設計図通りに配置してください。
Please arrange the spacing of the main reinforcement exactly as shown in the design drawing.