珠江水下沉管隧道的抗震分析与设计(Ⅰ)──时程响应法

ASEISMIC ANALYSIS AND DESIGN OF THEPEARL RIVER TUNNEL (I)-TIME DOMAIN RESPONSE METHOD

研究沉管隧道在地震条件下整体受力的分析方法．分两步建立计算模型．第一步通过分析场地地基土切片的动力特性．根据等效原则将其化为等效单质点体系，然后在纵向用等效弹簧连接而成为多质点体系的地基土计算模型；第二步将隧道看作弹性地基梁与上述多质点体系通过等效弹簧连结而得到土一隧道体系的计算模型．本文结合广州黄沙一芳村珠江水下隧道工程实例建立了具体的计算模型并对多种不同的约束条件，进行了纵向与横向地震响应时程分析，为该隧道的抗震设计提供依据．

This paper deals with seismic response of a tunnel-soil system. Immersed tunnel, as anunderground structure, must be compatible with the deformation of the surrounding soil. Thus'the simplified model for a tunnel-soil system is established through two steps. At the first step, anMDOF system is developed for modeling the foundation soil. To this end, dynamic behavior ofthe foundation soil is analyzed. A typical section of the foundation soil simplified as a single massspring system on the basis of some equivalent criteria. Those mass are linked longitudinally by elastic springs to form an MDOF system. At the second step, the tunnel is treated as a beam on elastic foundation; that is, the tunnel is connected with the soil massed to form a tunnel-soil system. This model has been applied to the seismic analysis of Huangsha-Fangcun immersed tunnelacross the Pearl River in Guangzhou. align recommendation is Proud on the basis of this analysis.