短语词组短語curved steel beam 曲線鋼梁flat curved box beam 扁平曲線箱梁curved -beam element 曲梁單元curved plate beam element 曲板板梁單元curved cantilever beam 懸臂曲梁space curved -beam 空間曲梁curved elastic beam 彈性曲梁 返回 curved beam