首台超临界百万机组干煤棚网壳施工探讨

干煤棚是火电厂中存储煤的一种大型棚库,为了满足储存和斗轮机作业空间,要求跨度大、净空高.浙江华能玉环发电厂(4×1 000 MW)燃煤机组是国内首台百万机组,配置干煤棚2座,结构形式为双层网壳,网壳跨度103 m,净高38 m,属超大型网壳结构.结构跨度较大,没有成熟经验可供参考;工期紧,需要合理安排施工工序;脚手架类型的选择和搭设方案是最大的难点所在;施工现场场地狭小,现场运输量大.本工程施工以大型脚手架为依托搭建滑移施工平台,采用高空散装法分段安装,在完成网壳安装、防腐施工、屋面板安装之后,将脚手架滑移到下一个分段继续施工,直到完成全部施工任务.

Discussion on construction of dry coal shed reticulate shell for first supercritical megawatts unit

Dry coal shed is one kind of large shed storehouse for depositing the coal in a fossil-fired power plant.To meet the need of store and working space of bucket wheel stalker,the span and clear height should be large.The coal-fired unit of Huaneng Yuhuan Power Plant(4×1000 MW) in Zhejiang Province is the first domestic megawatts unit which deploys two dry coal shed reticulate shell,of which the structural form is double reticulate shell.The shell has a large span of 103 m,and a clear height of 38 m;it is a super reticulate shell structure.The span of the structure is very large and there is no mature experience to draw lessons from.Because of the short construction period arranging the construction processes reasonably is very necessary.The most difficult thing is to choose the scaffolding and erection program.Construction site is narrow and the traffic volume in site is large.Relying on the large scaffolding to build the gliding construction platform in the construction process; in this project,the method that is adopted is bulk way with high altitude to lift segment by segment.After shell installation,anti-corrosion construction and roof board installation,scaffolding is slipped to the next segment to go on the construction.It won't stop until the construction task has been finished.