高烈度地震山区铁路减灾选线技术

为从源头上减轻高烈度地震山区的铁路灾害,针对选线设计中廊道方案选择和空间定线,从风险调控的理念,研究了减灾选线技术.采用断裂构造地貌理论,对活动断裂塑造的地貌格局和强震灾害效应进行了综合分析,得出了廊道方案选择原则.根据波动理论,对芦山、汶川地震等表现出的地震波传播的地形效应进行分析,提出了空间定线要点.研究结果表明:逆断层下盘挠曲盆地、正断层上盘断陷盆地、走滑断层断陷盆地和拉分盆地,均是铁路廊道方案可利用的地貌单元.确定大段落线路高程时,可不考虑高程放大效应;峡谷地形线路应避免布置在地震波入射方向一侧;近场区线路应选择在地震波传播的迎坡向,远场区在背坡向;应尽量避免设置小半径曲线,凸曲线应避免设置深路堑或高大支挡工程. 

Disaster Reduction Techniques of Railway Route Selection in Mountainous Regions with High Earthquake Intensity

To reduce earthquake-induced disasters of railway in mountainous regions with a high earthquake intensity from fountainhead, the disaster reduction techniques of the selection of transportation corridors and the space layout of railway lines, were researched based on the concept of risk control. From the fault tectonic geomorphology theory, landform patterns formed by active faults and seismic disasters were analyzed, and the selection principles of transportation corridors were obtained. From the wave motion theory, the topography effects of seismic wave propagation reflected in the Lushan and Wenchuan earthquakes were analyzed, and the key points of line space layout were worked out. The research result shows that lexural basin on footwall of reversed faults, rift basin on hanging wall of normal faults, and rift basin and pull-apart basin on strike-slip faults are available geomorphic units of railway corridors. Elevation amplification effect may not be considered in the route elevation determination of large sections. Canyon routes shall be avoided laying in the incident side of seismic waves. Earthquake near-field routes shall be selected along the hillside facing wave propagation direction, while far-field routes in the opposite side. Sharp curves must be avoided, moreover, deep cutting slopes and tall retaining structures shall be avoided layouting in the convex side of a curve.