Low-construction-emission cross-section optimization for mountainous highway alignment designs

Abstract

Designing low-construction-emission cross-sections of mountainous highway alignments is challenging. To address this issue, this paper develops a framework of cross-section optimization for highway alignment (COHA) to minimize the construction costs and emissions of the mountainous highway. First, COHA enumerates the earthwork costs of all possible highway cross-section locations in each cross-section profile. Second, we classify cross-sections into two categories, sensitive and nonsensitive cross-sections, with stochastic dominance (SD) theory and a complete ranking method. Third, to obtain the final optimized highway alignment, the initial alignment determined by optimal cross-sections is fitted by the weighted least square method with two dimensions. Finally, this methodology is applied to a real-world case study in a mountainous region, and the results verify that COHA can automatically optimize highway alignment, decreasing carbon dioxide emissions and land use by 3.6 % and 3.1 %, respectively, compared with manual work.