软基上大型泵站及基础抗震关键技术研究

基于南水北调东线睢宁二站工程,针对强震区软基上大型泵站特点,研究建立了地基-泵站结构的整体三维有限元抗震分析模型,通过计算分析、方案对比,提出整体式结构布置、灌注桩加锚杆的连续墙基础加固方案,提出施工过程中张拉锚杆预应力以保证深基坑稳定性,完建后释放锚杆预应力,使整个泵站、检修间、控制室、地连墙构成一个类似半埋式的地下结构,全面解决了睢宁二站软基上泵站抗震的关键技术问题。研究方法和研究成果可供睢宁二站及同类软基上大型泵站抗震设计参考。

Study on key aseismic technology of large-scale pumping station and its base on soft foundation

A full 3D finite-element aseismic analysis model is developed for foundation-pumping station structure of Suining pumping station II of the east route south-to-north water transfer project,a large-scale pumping station on soft foundation in a meizoseismal area.Through analysis of computations and comparison of alternative schemes,a reinforcing scheme that adopts underground continuous wall foundation of an integral structure layout and anchor bolts-bored piles,is recommended,and a scheme of prestressed anchor bolts being tensioned at the construction stage is proposed to ensure stability of the deep foundation pit.The prestress of anchor bolts will be released after completion of the construction,so that the whole pumping station,maintenance room,control room and underground continuous wall can form a similar half-buried underground structure.Thus the key aseismic technical problems of this pumping station are completely resolved,and the proposed methods and results provide a technical support to the aseismic design of Suining pumping Ⅱ and the other pumping stations with soft foundation.