【摘要】 为探讨地下结构近距离穿越地表结构时二者之间地震响应的相互影响规律,建立隧道–土体–地表框架结构相互作用体系计算模型,系统研究对该体系地震响应影响显著的参数,具体包括:隧道的直径和埋深、土体的分层特性、框架结构的高宽比及其与隧道圆心的间距、输入地震波特性等。计算分析表明:(1)隧道对体系自振特性影响并不显著,但地表框架结构则显著改变了体系的频率特征;(2)隧道对地表框架结构地震响应的影响主要与隧道的半径相关,较大的隧道半径可阻隔地震波的传播,从而起到一定的减震功能;(3)由于考虑的框架结构质量相对较轻,地表框架结构对隧道地震响应的影响不显著;(4)由于地震波频谱成分及结构自身频率的影响,不同地震波对体系地震响应的影响十分显著;(5)土的分层特性改变了土体的刚度,因而也影响了体系的地震响应。研究成果可为初步定性确定地下结构与临近地表结构地震响应的相互影响提供参考。更多还原

【Abstract】 In order to investigate the mutual influence of the seismic responses from the underground structure and above ground structure,a computation model containing a system of the tunnel,the ground soil and the adjacent structures was established. The key factors influencing the seismic responses of the system were studied,including the depth and radius of tunnel,the features of layered soils,the height to width ratio of the super structure,the distance from the super structure to the axis of tunnel and the characteristics of the input seismic waves. The calculated results showed that the existence of tunnel had almost no influence on the natural frequency of the system,while the super structure had a significant influence on the frequency character of the system. The main factor of tunnel influencing the super structure was the radius of tunnel because the tunnel with larger radius blocked more prominently the propagation of seismic wave leading to some degree of shock absorption. Theinfluence of super structure on the seismic response tunnel was insignificant because the weight of the super structure considered in the paper was very light. The characteristics of input seismic waves had significant effect on the seismic response of the system due to the frequency contents and frequencies of the super structure. The seismic responses of the system were influenced by the soil properties.更多还原