Spatial multi criteria analysis of ground conditions in early stages railway planning using analytical hierarchy process applied to viaduct-type rail in Southern Sweden.

Abstract

This study applies a spatial multi-criteria analysis to assess ground suitability for pier-supported viaduct railways using the Analytical Hierarchy Process (AHP). By integrating expert judgments, the analysis evaluates six key geotechnical categories—soil type, soil depth, rock type, slope, wetness index, and groundwater occurrence—to map ground suitability. Three weight normalisation methods were tested to explore how different normalisation approaches affect the resulting suitability assessments. The results reveal significant variations in suitability maps, highlighting how different expert weighting strategies can influence decision-making during early-stage railway planning. Uncertainty maps were generated and used to identify areas requiring further investigation. The methodology is applied to an area in Southern Sweden, between the cities of Lund and Hässleholm to compare the weighting strategies over a relevant and geologically diverse area. A practical application comparing foundation types along identified routes showed that AHP-guided pathfinding achieved a clear preference for ground conditions suitable for non-piled foundations compared to a reference line. The method provides a systematic framework for preliminary geotechnical evaluations in railway planning, enabling more focused site investigations and supporting industrialized construction approaches.