沉管隧道地震响应分析的等效质点系模型探讨

条装地下结构如隧道、各种埋设管道等一般可看作弹性地基梁进行静力及动力分析。在地震条件下，结构与土相互作用，但土的振动成为主要因素。为分析土的地震响应需把基土这一三维连续体作简化处理，简化成为等效多质点模型。本文着重探讨这种简化模型的建立方法，推导等效方法，通过几种简化体系的分析比较，论证单质点串体系的合理性，并将其应用到广州黄沙－芳村珠江水下隧道工程的地震响应分析，为抗震设计提供依据。

A STUDY OF THE EQUIVALENT MASS-SYSTEM MODELSFOR THE ANALYSIS OF EARTHQUAKE RESPONSEOF AN IMMERSED TUNNEL

Strip-shape underground structures such as the tunnels and tubes for various uses canbe treated as a beam on elastic foundation. Under earthquake condition, although there exists soilstructure interaction, the foundation soil vibration is dominant. In other words, analysis of earthquake response of the soil is essential. To this end, simplified models, (i. e. equivalent mass system models based on some equivalence criteria) are proposed, instead of a general 3-D continuummodel. In this study, equivalence criteria are proposed and the simplified models are compared.The single-mass-string model is proved to be valid and therefore applied to the analysis of earthquake response of the Pearl River Immersed Tunnel.