Design of 'minimum energy' culvert sections

• Main Author: Muhammad Isnin Akahmat.
• Other Authors: Shuy Eng Ban
• Format: Final Year Project
• Language: English
• Published: 2009
• Subjects: DRNTU::Engineering::Civil engineering::Water resources
• Online Access: http://hdl.handle.net/10356/16316
• Institution: Nanyang Technological University

Culverts are expensive structures to construct, especially if their construction entails tunnelling through high grounds. The conventional practice in Singapore is to design a culvert to have the same section as the storm channels upstream and downstream of the culvert, so as to maintain uniform flow through the culvert section. Hydraulically it is possible to design a culvert with a smaller section, allowing the flood flow to pass through at a higher velocity and Froude number, without causing substantial flow back-up upstream. This can be achieved by designing the culvert with a slightly depressed bed. The culvert width can also be reduced further, which in turn could reduce the overall cost of culvert construction. The culvert section can be optimally reduced by passing the flood flow through at near critical flow conditions, or at near minimum specific energy. However steps must be taken to ensure that the flow will not reach super critical flow and turbulent which is undesirable. This project is to investigate the feasibility of adopting such ‘minimum energy’ culvert design sections in Singapore. This is done by running a simulation program using a software called Hydraulic Engineering Centre – River Analysis System (HEC-RAS). The final aim is to propose the optimum design of the culverts in achieving the objective of this project. Finally, the results of the simulation, the problems encountered during the study, a review of the application and future enhancement are discussed in details in several chapters of this report.