Research conclusions：Based on scheme analysis of introducing Guiyang-Guangzhou line into the hub, the paper identifies the reasonable recommended scheme by linking Guiyang station with passenger external line. By demonstration and comparison of the extension plans of introducing Guiyang-Guangzhou line into the Guiyang Station, the paper identifies the plane introducing scheme, analyzes the using of arrival and departure tracks and other issues, proposes the scheme selection principles of introducing passenger dedicated line into the existing station under normal condition: (1) When the terrain condition is better and other restricted conditions are less, the partitioned layout form of high speed and common speed field can be preferred.(2) When the terrain, demolition and other constraints restrict introducing, the elevated station can be adopted. (3) When the restriction conditions are more, and the existing lines need to be made full use of, the plane connection way can be used, especially for larger intermediate station and passenger station and the economical and practical of the scheme should be fully studied. (4) The research conclusion has the actual reference significance for scheme of introducing passenger dedicated line into existing station.

Research conclusions：(1)The sharing law of train loads is not effected by the axle loads and the structure of subgrade, train loads are shared by 5 sleepers for single axle wheel, shared by 8 to 9 sleepers for double axle wheels and shared by 15 sleepers for four axle wheels.(2)Wherever the axle load is acted directly above or on any position between the two sleepers, the shape，size and properties of Gauss function curve fited for the loads sharing remain the same, only the position moves as the position of the axle loads.(3)Under single axle wheel the stress ratio between dynamic stress produced by train loads and gravity stress of subgrade is about 0.2 which meet the design principle, while under multi axle wheels the ratio is between 0.3 to 0.5 which does not meet the design principle. (4)The above conclusions have important guiding significance to the structure design of heavy haul railway subgrade.

Research conclusions：(1)The internal force calculation and deformation of foundation pile are based on the structure unit, foundation slab and pile are treaded as a whole, and think that foundation slab，pile and foundation can coordinate deformation in the upper loads and the elastic resistance of foundation. The calculation method can better reflect the characteristics of foundation pile in stress and deformation. (2) Pile space in the vertical retaining wall is magnified on resisting lateral deformation, so the distance from pile edge to the bottom edge should be controlled to meet the minimum construction. (3) Alternative framework method adopted in foundation slab greatly simplifies the calculation work, the results of alternative framework method is reliable.(4) The cantilever retaining wall with pile foundation can avoid the adverse effect of excavation and ground improvement on existing subgrade, and greatly reduce construction interference on movement of the train, the retaining wall has higher comprehensive economic and technical benefits.(5)The research results can be promoted and used for the design of retaining wall which is limited with construction space and lower sub grade bearing capacity.

Abstract：Research purposes：Planning analysis is the basis for  environmental impact analysis, prediction and evaluation of the Planning Environmental Impact Assessment (PEIA), especially  analysis of planning and coordination is the key point. On the occasion of "Technical Guidelines Master of Planning Environmental Impact Assessment " is promulgated, based on the collection of a lot of detailed current situation data, as an example of the intercity railway network plan of Guanzhong City Group, this paper systematically studied  the planning analysis of PEIA, which can be a reference for the railway network PEIA.
Research conclusions：Through analysis of the PEIA, we can drawn  the following conclusions: (1)Using the analogy method, overlay method, scenario analysis method and so on, the environmental capacity in the planning area of the intercity railway network is identified. (2) From the data collection and field investigation in the planning area, it shows that the key environment and resource factors, which restrict the intercity railway network planning and implementation, are land resources, ecologically sensitive areas, water resources, artifacts, rare and endangered animals and plants, and so on. (3) The coordination between the railway network planning and other relevant planning are analyzed, which is relied on many different sights, for example planning and resource conservation, the coexistence of the environmental protection and urban development coordinating, and so on. The impacts of inter-city rail network on the national policies, planning, and regional planning are clear. (4) The analysis of the planning uncertainty is given to ensure the scientific conclusions.（5）The research results can be a guidance and reference in the intercity railway network planning and also have positive references for  environmental impact assessment in the similar railway network plan.
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