不同列车激励下辽代古塔振动响应研究与评估

Research and Evaluation of Vibration Responses of Ancient Pagoda of Liao Dynasty under Different Train Excitation

以北京辽代良乡塔为研究对象,测试不同列车作用下良乡塔水平方向的振动响应,建立ANSYS有限元模型,通过现场测试与数值模拟,分析列车影响下结构的振动速度最大值,并对列车影响下结构的振动响应进行评估。得到以下结果:(1)良乡塔在客运和货运列车作用下,每层振动速度响应随层高逐渐增大;(2)良乡塔在货运列车作用下的振动速度响应要大于客运列车。良乡塔在客运列车作用影响下最高承重处的振动速度最大值为0.053 mm/s,其完整性和安全性均处于规范限值内;(3)在货运列车作用影响最高承重处的振动速度最大值为0.146 mm/s,在建筑完整性上接近规范限值0.15 mm/s,考虑该辽代古塔的文化价值,需对其完整性加强监测与保护。

Taking the Liangxiang pagoda of Liao Dynasty in Beijing as the research object,the vibration responses in horizontal direction of the pagoda under the action of different trains are tested.The ANSYS finite element model is established.Through the field test and numerical simulation,the maximum of vibration velocity of the structure under the effect of trains is analyzed,and the corresponding vibration response of the structure is evaluated.The following results are obtained:(1)Under the action of passenger and freight trains,the vibration speed response of the floors of the Liangxiang tower increases with the floor altitude increasing;(2)The vibration speed response of the Liangxiang tower under the action of freight train is greater than that of passenger train,the peak vibration velocity of the Liangxiang pagoda at the highest loadbearing position is 0.053 mm/s under the excitation of passenger trains,which is less than the allowable value in the standard and means that the architectural integrity and structural safety of the ancient pagoda meet the requirements;(3)The peak vibration velocity of the Liangxiang pagoda under the excitation of freight trains is 0.146 mm/s at the highest load-bearing position,which is close to the allowable value of 0.15 mm/s in the standard for the architectural integrity.Considering the cultural value of the Ancient Pagoda of Liao Dynasty,it is necessary to strengthen the monitoring and protection of the integrity of the pagoda.