bar joist

例句：

1. 1. The engineer designed the bridge to withstand heavy loads.
   工程师设计这座桥能够承受重载。
2. 2.The construction of the bridge required the installation of several bar joists.
   建造这座桥需要安装几根梁。
3. 3. The beams of the roof are made from strong materials to support the weight of the building.
   屋顶的梁是用坚固的材料制成的，以支撑建筑物的重量。