Responsive transport network design: minimal investment for desired travel time reduction

It is crucial for policymakers to satisfy the expectation of network users in practice. It is a so-called responsive transport network design problem. It is curious that this important problem is rarely explored. This paper aims to propose a method to solve this problem. A novel bi-level programming model is formulated where the upper level is to minimize investment cost with desired travel time reduction target, while the lower level is transport system equilibrium that is a closed-loop feedback process between destination choice and traffic assignment. It is well known that the solution of bi-level programming model is challenging. A trial and error algorithm is designed to solve the proposed model. Finally, a computational experiment is carried out to demonstrate the effectiveness and operability of the proposed method and algorithm. Results show that they are useful tools for investment decision making on target-oriented transport network design.