河源断裂带对京九高速铁路工程安全影响研究

Research on the Influence of Heyuan Fault Zone on the Safety of Beijing-Jiulong High Speed Railway Construction

研究目的：京九高速铁路沿河源活动断裂带行进，河源断裂带为发震断裂，曾因新丰江水库蓄水发生过国内唯一的水库诱发破坏性地震。河源断裂带的活动性对高速铁路线路位置以及工程措施的选择具有重要影响。本文通过资料收集、遥感解译、野外地质调查，结合物探、钻探、断层物质测年等综合勘察方法，对河源断裂带的结构、发震特征及其对京九高铁的影响进行研究探讨。 研究结论：（1）河源断裂带主断裂分为南段、中段和北段三个支断裂，总体倾向南东，倾角在30°～60°之间；（2）河源断裂为第四纪早一中更新世断裂，非全新世活动断裂；（3）河源断裂带沿线发生的地震主要集中于主断裂中段靠近新丰江水库附近，地震活动主要为水库诱发地震，为浅源地震；（4）河源断裂带中段地震活动频繁，加之东江冲积平原松散覆盖层对振动有放大作用，结构容易形成疲劳损害，宜对该区域抗震设防等级提高一级；（5）河源断裂带两盘有缓慢变化的差异沉降，建议以高速铁路低填路堤形式跨越河源主断裂北段，并加强路堤本体及边坡柔性防护措施；（6）线路跨过河源主断裂后，距离断裂较远的右侧方案可较好地规避河源断裂带及其次级断裂形成的破碎带的影响；（7）该研究成果可为穿越活动断裂带的高速铁路选线与设计提供借鉴和参考。

Research purposes： Beijing -Jiulong High Speed Railway is designed to travel along Heyuan Fault Zone, which is an active earth -triggering fault, and triggered the only reservoir induced destructive earthquake as a result of the impoundment of Xinfengjiang Reservoir. The activeness of Heyuan Fault Zone has a great effect on the line location and engineering measures of high speed railway. Based on data collection, remote sensing interpretation and field geological survey, combined with geophysical prospecting, drilling, fault material survey and other comprehensive survey methods, this paper studies the structure, earthquake features of Heyuan Fault Zone, as well as the influence on high speed railways. Research conclusions： （1）Heyuan Fault Zone, with the southeast trend and the dip ranging from 30° -60°, is constituted by three branch faults, which are south part, middle part and north part. （2） Heyuan Fault Zone formed during early to middle Pleistocene of Quaternary, not during Holocene of Quaternary. （ 3 ） Earthquakes, which concentrate mainly on the middle part of the fault zone, close to Xinfengjiang Reservoir, are manly induced by the reservoir, and can be classified as shallow - focus earthquakes. （4）Because the earthquakes in the middle part ofHeyuan Fault Zone are very criterion should be raised by active, and the Quaternary loose bed will magnify the vibration, seismic fortification one level. （5）There is an insensible differential settlement between the two walls of the fault, and the low filled subgrade is a better engineering method for the railway. The subgrade and slope can be defended with flexible structures. （6）The right line, which has a greater distance from the fault, can avoid the fracture zones caused by Heyuan Fault and its secondary faults. （7）The research results can provide a certain reference to high speed railway route selection and construction passing through active fault.