duplicated rod

• 复式拉杆

duplicated rod的用法和样例：

例句

1. The pull rod is screwed into the inside thread of the anchor head.
   将拉杆旋入锚头内的丝扣。
2. Large span double box-beam rod structure is born out of BSS.
   大跨度双箱梁钢棒拉杆组合钢结构即脱胎于张弦梁结构。