one of the cross braces that support the rails on a railway track;
"the British call a railroad tie a sleeper"
例句
用作名词 (n.)
The other key technique in using an on-train GPR deals with the estimation and elimination of the influence of reinforcing steel bar in the cement crosstie. 如何确定和消除枕木中的条状钢筋对地下目标检测的影响也是车载探地雷达的关键技术之一。