多年冻土区桥梁桩基础地震响应的模型振动试验研究

以青藏铁路高温不稳定多年冻土区"以桥代路"工程——清水河特大桥的桩基础为研究目标,在负温条件下对该桥梁桩基础结构的缩尺模型进行了地震荷载作用的模型振动试验,研究了地震荷载作用下桩-冻土相互作用,分析了结构的地震响应特征,明确了桩体动荷响应对桩周冻土地温和应变的影响规律,最后对地震荷载作用下高温不稳定多年冻土区桥梁桩基础的稳定性作出了评价.

Study on Shaking Table Test for Seismic Response of Pile Foundation of Bridges at the Permafrost Regions

Based on the research project of pile foundation of the Qingshui River Bridge, which is a typical engineering named by "bridge instead of road" and locates at high temperature and insta-bility permafrost region along the Qinghai - Tibet Railway. Under seismic dynamic loading, the shaking table test for the scale model of the piles is carried out when the soil temperature around model piles is below 0℃. The interaction between piles and frozen soil under seismic loading is researched, and the characteristics of seismic response of the pile structure are analyzed. Moreo-ver, that the effect law of dynamic loading response of the piles on temperature and strain around piles is achieved, and the stability of the pile foundation of bridges at high temperature and insta-bility permafrost region is evaluated as well.