Initiation of sediment motion in the presence of vegetation

• Main Author: Lee, Marilyn Wan Xin
• Other Authors: Cheng Niansheng
• Format: Final Year Project
• Language: English
• Published: 2017
• Subjects: DRNTU::Engineering::Civil engineering::Water resources
• Online Access: http://hdl.handle.net/10356/71308
• Institution: Nanyang Technological University

It has become increasingly important to explore the effects of vegetation in the river as it helps with water management and aid in the improvement of the environment. In this project, the effects of sediment transport in an open channel with submerged rigid vegetation represented by rigid cylindrical rods were explored. Through experimental observations, the difference between the initiation of sediment motion between vegetated and non-vegetated beds were investigated. The experiments conducted focused on the amount of sediments collected over a time span. Four different arrangements were set up varying spacing between the rods to simulate four different densities of vegetation. For vegetated beds, scouring was observed. Data obtained for the critical flow discharge and sediment transport rate were used to determine the critical flow velocity for the vegetated bed. The experimental results indicated that vegetation density played a significant role in the initiation of sediment motion where the increase in density resulted in a decrease in critical velocity.