青荣城际铁路跨线断裂的活动性研究

On the Activity of Fault Zone Crossing Qing-Rong Intercity Railway

青荣城际铁路沿线断裂构造发育,未来断裂活动会否对铁路建设产生变形破坏必须进行研究.利用优势面理论和神经网络方法评判出桃村跨线断裂对工程场地的稳定性影响最大.选取桃村断裂带断层泥的石英颗粒进行显微溶蚀构造测年,采用模糊综合评判研究了石英颗粒表层的机械微特征.结果显示,桃村断层最晚活动时间分布在更新世早、中期,活动方式以快速发震为主,为非活动断层,不对城际铁路构成安全危险.分析结果与该断层的宏观特征判断相近.通过对跨线断裂上路基沉降变形的长效监控,判定断裂带线下工程的沉降趋于稳定,具备沉降评估和铺轨条件,解决了高速铁路跨越断裂带的稳定性问题.

Fault structures along Qing-Rong intercity railway lines is well developed. Whether the faults active or not in the future,which result in great deformation and destruction on Qing-Rong intercity railway must be studied. The Taocun fault zone crossing Qing-Rong Railway is judged to plays the most significant role on the stability of engineering ground by preferred plane theory and artificial neural network( ANN) technique. Combining the identification of the SEM characteristics with the fuzzy comprehensive evaluation statistics of mechanical effect on the surface of quartz grains from the Taocun fault zone,it indicates that the strong fault's activities has taken place between the early and middle Pleistocene,with the strick-slip predominated.Therefore,it's a inactive fault which does not affect the project safety. These results are in accordance with the fault macroscopic characteristic analysis. According to the long-term roadbed settlement monitoring,underline settlement of high speed railway crossing fault zone tends to stable,which met the demand of sediment assessment and laying the ballst track. The results demonstrate that stability problem of fault zone crossing high speed railway has been solved effectively.