ll Number: AIT Thesis no.EV-85 Kreeta Sroikeeree

Least cost design of drainage systems with three-dimensional state variables - Bangkok : Asian Institute of Technology, 1985 - 51, (39) p. - Thesis ; no. EV-85-15 . - Asian Institute of Technology. Thesis ; no. EV-85-15 .

A thesis submitted in partial fulfillment of requirements for the degree of Master of Engineering, School of Environment, Resources and Development

Thesis (M.Eng.) - Asian Institute of Technology, 1985

Drainage systems can be efficiently designed for minimum cost by Dynamic Programing. Present models generally use a one-dimensional state variable with the pipe level as parameter. Although the theoretical need for at least a two-dimensional state variable is recognised, more dimensional state variables are still considered as impracticable due to computational requirements. In this study one-, two-, and three-dimensional models were developed. The parameters are the pipe elevation, the pipe diameter, and the time of flow as in the Rational Method. The model has been implemented on a IBM personal computer. Three test examples show the operationability of the developed program. It has been found for the test examples that introducing the time of flow into the state variable reduces the least cost between 0 and 7.2%. Depending on topography, introducing the diameter in some certain cases reduces the least cost more than 17%


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