1000kV GIS设备基础设计研究与优化

Design Study and Optimization of 1 000 kV GIS Foundation

1 000 kV GIS设备在变电站里重要性极高,对沉降变形极为敏感,为保证设备的顺利安装、正常运行及使用,厂家对1 000 kV GIS设备基础提出的不均匀沉降、施工误差等要求均较常规工程高,而沪西站地处软土地区,场地内普遍分布有厚约10 m的③淤泥质粉质粘土,同时有近3 m厚的回填土,极易引起GIS设备的不均匀沉降。根据工艺要求,1 000 kV GIS设备基础表面需采用大平板,在基础长度、宽度均较大的情况下,大体积混凝土的施工、表面裂缝的控制也是1 000 kV GIS设备基础设计的一大难点。采用Pile 7.1桩基础设计计算软件计算沉降,在不均匀沉降满足设备要求的情况下,对筏板厚度及桩基布置进行优化。结合工程经验,采用双层埋件,减小埋件施工误差控制的难度,并根据1 000 kV GIS设备基础的特点,采取各种措施减小大体积混凝土施工的影响及基础表面的温度裂缝。

The 1 000 kV GIS equipments has a very high importance in substation, it is extremely sensitive on the set- tlement deformation. To ensure the equipment installed successfully, operated and used normally, the asymmetry set- tlement and construction error requirements of the 1 000 kV GIS equipments is higher than the conventional engineer- ing requirements. The Huxi substation is located in soft soil region, about 10 m thick silty clay and nearly 3 m thick backfill are generally distributed within the substation. It is extremely easy to cause the asymmetry settlement of the GIS equipment. According to the technical requirement, the foundation surface of 1 000 kV GIS equipments need to use large fiat plate. The mass concrete construction and surface crack control is also a design difficulty because of the 1 000 kV GIS foundationg large length and width. This paper uses the Pile 7.1 pile foundation design and calculation software for computing settlement. While the asymmetry settlement satisfying the requirement of the 1 000 kV GIS e- quipment, the thickness of raft foundation and pile layout is optimized. According to the engineering experiences, double embedded parts is used to reduce the construction error control difficult, and various measures was taken to re- duce the influence of the mass concrete construction and the base surface thermal crack.