短語詞組短語beam with web openings 開孔梁beam without web reinforcement 無腹筋梁restrained beam with web reinforcement 有腹筋約束梁composite beam with web openings 帶腹板開洞組合梁restrained beam without web reinforcement 無腹筋約束梁beam with corrugated web 波折腹板梁beam web plate 梁腹板beam web plates 梁腹板 返回 beam web