【作者】 蒋丽忠； 冯玉林； 周旺保； 聂磊鑫； 谭志化； 张云泰； 郑兰；

【Author】 JIANG Li-zhong;FENG Yu-lin;ZHOU Wang-bao;NIE Lei-xin;TAN Zhi-hua;ZHANG Yun-tai;ZHENG Lan;School of Civil Engineering, Central South University;National Engineering Laboratory for High Speed Railway Construction, Central South University;

【机构】 中南大学土木工程学院； 中南大学高速铁路建造技术国家工程实验室；

【摘要】 为研究近断层脉冲型强震对高铁桥梁路基轨道系统的地震响应特点,以高速铁路连续梁桥、两端引桥、路基、CRTS II型板式无砟轨道(HBSCST)组成的整体系统为例,基于有限元方法建立两种HBSCST模型,选择具有破裂前方脉冲、滑冲脉冲和无脉冲的近断层地震动作为输入。提取两种HBSCST模型中的制动墩、引桥桥墩墩顶位移时程及系统各层位移最值进行对比验证,进而分析脉冲运动对HBSCST模型地震响应的影响。研究表明:两种仿真模型计算结果吻合良好,验证了模型的有效性;纵、横桥向激励下,系统各层纵、横向位移包络图均趋于一致,纵桥向激励下,无脉冲地震动下系统各层响应最大,破裂前方脉冲次之,滑冲脉冲最低;横桥向激励下,破裂方向脉冲地震动下系统各层响应最大,滑冲脉冲次之,无脉冲最低,破裂前方脉冲地震动对系统各层响应的影响在纵,横桥向激励下均大于滑冲脉冲;随着PGV/PGA值的增大,三组地震作用下系统各层的纵、横向位移最大值基本呈增大的趋势。更多还原

【Abstract】 In order to study the seismic response characteristics of near-fault pulse-type strong earthquake to High-Speed railway bridge subgrade track system(HBSCST), two HBSCST models were established based on the FEM. The time history of the brake pier and approach bridge pier top displacement, and the maximum displacement of system each layer in the two HBSCST models were extracted for comparative verification, then the impact of pulse motion on the HBSCST seismic response was analyzed. The results of the two models agree well with each other, which verifies the validity of the models. Under longitudinal and transverse bridge excitation, the longitudinal and transverse displacement envelope diagrams of all layers of the system tend to be consistent. Under longitudinal bridge excitation, the response of system each layer is the highest under the pulse-free ground motion, followed by the forward-directivity pulse, and the fling-step pulse is the lowest. Under transverse bridge excitation, the response of each layer of the system is the highest under the forward-directivity pulse, followed by the impulse of the fling-step pulse, and the pulse-free ground motion is the lowest. With the increase of PGV/PGA value, the maximum displacements of system each layer basically show an increasing trend under three groups of earthquakes.更多还原