短語詞組短語lower chord member support 下承式bottom chord member 下弦桿chord member of truss 桁架弦桿top chord member 上弦桿compressive chord member 受壓弦桿upper chord member 上弦桿件;上弦桿main chord member 主弦桿chord member with integral joints 整體節(jié)點弦桿integral joints of chord member 整體節(jié)點弦桿 返回 chord member