Geological Route Selection Of Railway Along High Seismic Moutain Region In Southwest China

In topography, railway in southwest region crosses plain, high mountain and valley; in geological structure, it crosses the Dl fault zone, west D3fold and fault zone. The structure background is complicated, the inner and outer dynamic geological effect is intense. Unfavorable geology is wide in distribution, various in types and large in scale. Complex topographical and geological conditions bring serious challenge to railway route selection. Based on the special geological areas and geological environment in the region where the railway goes through, the research on geological route selection in mountain areas with high intensity earthquake is of important guiding significance.Based on regional geological background of railway, the paper analyses the main factors of controlling railway geological route selection (including topography, earthquakes, active faults and secondary geological disasters). These factors have a significant influence on geological route selection of railway. The study firstly introduces macro-trend of railway, comprehensively compared and selected two macro-trend schemes of the route which mainly combined with the geological conditions.According to the controlling factors of geological route selection of railway, combined with specific project examples, and based on the principles of geological route selection summed up by the predecessors, the following technologies of geological route selection have been put forward in the paper: i) route selection technology of active faults and earthquake fault zones, ii) route selection technology over mountain in mountain areas with high intensity earthquake, iii) valley ingression route selection technology and iv) route selection technology of adverse geological regions in mountain areas with high intensity earthquake. The alignment of route is determined when the route goes through three faults including Dl fault, D2fault and the west D3fault, the crossing mountain area, alpine gorge and plateau valley section, unfavorable geological region. So as to ensure the safe passing sections of railway at maximum degree, to reduce or avoid the damage to railway projects caused by earthquakes and secondary geological disasters.Through the research on geological route selection of railway in southwest region, a set of technologies of geological route selection suitable for mountain areas with high intensity earthquake have been summed up in the paper, the study results provide an important reference value for the future, how to solve the similar problem in case of railway passes through complex topographical and geological conditions areas.