channel cross section meaning in English

槽钢截面
河槽横断面

The changes in the channel cross sections between dam no . 3 and no . 4 mainly related to the opening depth applied at dam no . 3 and the scouring range extended with increasing opening depth
河床横断面之变化横断面的变化主要与坝坝体缺口拆除的深度有关，且坝体缺口深度愈深影响至上游淘刷范围的距离则愈远。
With same opening depth applied at dam no . 3 , deeper scouring hole was found at the downstream channel of dam no . 4 when the dam - conversion was conducted simultaneously . besides , the depth of downstream scouring hole of dam no . 4 increased with increasing opening depth at dam no . 3 . 3 . changes in the channel cross sections between dam no . 3 and no . 4
三号坝坝体拆坝的方式会对四号坝下游冲刷坑的深度会产生影响，由坝体相同断面的拆除，结果发现一次拆除会比分次拆除时造成冲刷坑的深度较深，而冲刷坑的深度会随著下游坝体拆除的深度增加而变大。