Bidirectional Dynamic Programming Approach for Highway Alignment Optimization

Abstract

In order to automatically generate the optimal highway alignment and avoid omitting valuable scenarios, a bidirectional dynamic programming approach for alignment optimization was put forward. Firstly we established a three-dimensional search grid in the study area. Then dynamic programming was used to find the best alignments within the vast study area. A double-direction searching strategy was proposed to obtain a group of scenarios ranking by their corresponding comprehensive cost. The alignments were then refined with Powell method so that the resulting alignments could deviate from the grid points to reach better solutions. Examples demonstrated that this approach can obtain global optimal alignment with good diversity.