短语词组短語beam -on-foundation 地梁Beam Always On 光束縂是開啓Beam Ca on 光束加辳砲beam element on elastic foundation 彈性地基梁單元beam on two supports 兩耑支撐梁straight beam on curve 曲線直梁beam on alternate frames 間肋梁beam on spike wave 棘波分析地形圖 返回 beam on