Keyword: «scours»

Underwater crossings of main pipelines are of great importance in the transport system of the country. Most underwater crossings are laid in an open-cut way by underwater trenching. Scours and sagging of the pipeline in the trench are common phenomena during operation. They lead to stress in the pipe wall. Its level increases with an increase in the length of the scoured section. Hence, protecting the underground crossing of the main pipeline from the impact of negative channel processes during their operation is crucial. The article shows that a comprehensive instrumental examination of the state of the underground crossing allows the detection of siphon denudation and the height of pipeline sagging. It has been established that the scours and denudations of the siphon are permanent.