Degree Type


Date of Award


Degree Name

Doctor of Philosophy


Civil, Construction, and Environmental Engineering


A state-of-the-art short-range transit planning technique was developed to help local planners evaluate the impacts of transit routing and scheduling options. A transit route evaluation procedure established route potential on the basis of demographic and transit service factors. The procedure was to provide a framework for selecting the best service policies to undertake when a reallocation of system resources was considered. The Des Moines Metropolitan Transit Authority (MTA) fixed-route system, a radial transit system, was selected for evaluating the transit use potential at the route level;A stiffness concept applied in structural analysis was used to estimate route ridership under varying supply conditions. The stiffness is more than trip generation from an area. Its function is to simultaneously measure a trip generation and distribution effect by incorporating both production and attraction capabilities along a route. Multiple regression techniques were valuable for sorting through the many eligible explanatory variables regarding transit ridership. The observation unit in regression analysis was a route-segment. Passenger density, the stiffness for each route-segment, was used as a dependent variable. Passenger density was represented by on-off-passengers per unit length of route-segment. The number of on-off-passengers is the sum of the number of on-passengers and the number of off-passengers. Frequency of service was always found to be the most significant independent variable. Other independent variables that are significant in explaining variations included population density, employment density, and travel time factor;A linear programming model was used to optimize the transit route on the basis of the demand and system constraints. The objective was to maximize the ridership in the system. The constraints included budget restriction, fuel supply, minimum and maximum service levels, and performance standards. The sensitivity analysis on the route stiffness provided a direction for allocating the limited resources among competing transit routes in an optimal way.



Digital Repository @ Iowa State University,

Copyright Owner

Richard Yun-Hao Woo



Proquest ID


File Format


File Size

118 pages