Method for mitigating silt blockage of confluence of main stream and tributary of mountain river

Abstract

The invention belongs to the technical field of water and sediment movement disaster reduction for mountain rivers, and provides a method for mitigating the silt blockage of the confluence of a main stream and a tributary of a mountain river. The steps are as follows: (1) the position of the concentrated flow route of the tributary meeting the main stream is surveyed when the tributary is in the normal water level period, and the position of the concentrated flow route of the tributary meeting the main stream and the maximum siltation thickness of the silt of the confluence of the main stream and the tributary after flood subsidence are surveyed when the tributary is in the flood period; (2) according to the surveys of step 1, at least two rows of water-blocking piers are arranged in the tributary, at least three water-blocking piers are arranged, and the position of each water-blocking pier needs to meet the following conditions: each water-blocking pier is located outside the position of the concentrated flow route of the tributary when the tributary is in the normal water level period, and each water-blocking pier is located within the position of the concentrated flow route of the tributary when the tributary is in the flood period. The method described by the invention can mitigate the adverse influence of the forced silt discharge phenomenon of the tributary on the flood carrying safety of the riverway and the configuration of the riverway, thus increasing the flood carrying safety of the riverway of the mountain river.

Description

technical field [0001] The invention belongs to the technical field of disaster mitigation of water and sand movement in mountainous rivers, and in particular relates to a method for alleviating sediment blockage in the confluence area of ​​main and tributary rivers in mountainous areas. Background technique [0002] The tributaries of mountainous rivers usually have no water or have small water flow. However, due to the large gradient of the tributaries of mountainous rivers, a large amount of water flow is easily formed in case of heavy rain, and floods occur. Significantly, such currents have a strong ability to carry sand. The areas where mountain rivers flow are mostly mountainous or plateau areas, with narrow and curved valleys and steep slopes. During heavy rain seasons, geological disasters such as landslides and mudslides often occur. In addition, the bed sand that constitutes the riverbeds of mountainous rivers is mostly rocks on both sides of the river. The weath...

AI Technical Summary

Problems solved by technology

At present, there is no report on the disaster reduction measures in the confluence area of ​​main and tributary rivers in mountainous areas under the condition of strong sediment transport. If a method can be developed to alleviate the sediment silting in the confluence area of ​​main and tributary rivers in mountainous areas, it will have a great impact on the safety of flood discharge in mountainous rivers. positive meaning

Images