高铁提速条件下路基不均匀沉降诱发的地基振动特性  

Ground vibration characteristics of high-speed railway induced by uneven settlement of subgrade with train speed increasing

作　　者：蒋红光 李宜欣 迟浩然 刘舜 梁明 姚占勇 Jiang Hongguang;Li Yixin;Chi Haoran;Liu Shun;Liang Ming;Yao Zhanyong(School of Qilu Transportation, Shandong University, Jinan 250002, China)

机构地区：[1]山东大学齐鲁交通学院,济南250002

出　　处：《东南大学学报（自然科学版）》2021年第3期442-448,共7页Journal of Southeast University：Natural Science Edition

基　　金：国家自然科学基金资助项目(51608306);教育部博士后科学基金资助项目(2016M590636);山东大学青年学者未来计划资助项目(2019WLJH60).

摘　　要：为了揭示高铁提速条件下路基不均匀沉降诱发的地基振动特性,建立了考虑路基不均匀沉降的列车轨道路基三维有限元动力分析模型.采用时域、频域分析方法获得了列车提速条件下典型路基不均匀沉降对地基振动传播的影响,并结合国内外环境振动控制标准讨论了列车提速的可行性.结果表明,路基不均匀沉降导致地基振动显著加剧,其水平横向和垂向的振动加速度分别增大了2.8和2.0倍.地基振动频谱响应以低频为主,其特征频率主要由单节车厢长度决定,无法反映路基表面不均匀沉降的波长特征.列车速度的提高导致地基振动响应加剧,但影响程度低于路基不均匀沉降.在现行规范中沉降波长20 m、幅值15 mm的限值下,当列车车速达到360 km/h时,周围环境的垂向Z振级已超过环境振动控制标准的要求,故高铁线路提速前需进一步评估路基平顺状态的影响.To reveal the foundation vibration characteristics induced by uneven settlement of subgrade with train speed increasing,a three-dimensional finite element dynamic analysis model of train-track-subgrade considering uneven settlement was established.The influence of typical uneven settlement of subgrade on the vibration propagation of foundation with train speed increasing was obtained by using the time-domain and frequency-domain analysis methods.The feasibility of train speed increasing was also discussed based on the domestic and foreign environmental vibration control standards.The results show that the uneven settlement of subgrade can lead to significant increase of foundation vibration.The horizontal and vertical vibration accelerations increase to 2.8 and 2.0 times,respectively.The spectrum response of foundation vibration is dominated by low frequency,and its characteristic frequency is mainly determined by the length of single carriage,which cannot reflect the wavelength characteristics of the uneven settlement on the subgrade surface.The increase of the train speed leads to the aggravation of foundation vibration,but its influence is lower than that of the subgrade uneven settlement.Under the limit of the settlement wavelength of 20 m and the amplitude of 15 mm in the current specifications,the vertical Z-vibration level at the vehicle speed of 360 km/h exceeds the environmental vibration requirements.Therefore,the effect of the smooth state of subgrade needs to be further evaluated before the speed is increased.

关 键 词：高速铁路 路基不均匀沉降 列车提速 地基振动 垂向Z振级 

分 类 号：TU435[建筑科学—岩土工程]