tractive load

例句：

1. 1. The heavy truck was pulling a tractive load of 50 tons.
   这辆重型卡车正在拖拽50吨的牵引负载。
2. 2.The train's tractive load is causing the wheels to slip.
   火车的牵引负载导致车轮打滑。
3. 3. The heavy load on the trailer caused it to pull with difficulty.
   拖车沉重的负载使它难以拉动。