built-up beam

例句：

1. 1.The engineer designed a built-up beam to support the weight of the building.
   工程师设计了一个组合梁来支撑建筑物的重量。
2. 2.The beam is made from a combination of steel and concrete.
   这个梁是由钢和混凝土混合制成的。
3. 3. The beam was constructed using advanced composite materials.
   这个梁使用了先进的复合材料进行建造。