混凝土桁架在侧煤仓结构优化中的应用

侧煤仓方案成为大机组主流,侧煤仓间横向框架主要有4列柱、3列柱、2列柱布置结构型式,其中以2列柱单跨结构布置的空间及投资最小.单跨布置时,框架跨度大,承受煤斗的荷载大,如何使结构合理经济成为结构方案布置的难点.某百万机组侧煤仓间的煤斗层梁采用混凝土桁架的结构方案,桁架具有受力合理、构造简单、自重较轻、材料节省、承载力高等优点.桁架的缺点是平面外刚度弱,很难通过自身的刚度抵抗水平地震力,结构布置中需采取措施解决桁架平面外刚度弱的问题.百万机组的侧煤仓间设置混凝土桁架比混凝土实腹梁有利于"强柱弱梁"的概念设计,对控制顶层位移、层间相对位移等有一定的优势,混凝土桁架方案比普通混凝土框架结构方案更利于抗震,可为类似工程提供参考.

Application of concrete truss to structural optimization of side bunker

The side bunker scheme becomes the mainstream for large units;the crosswise frame of the side bunker mainly has 4 colonnades,3 colonnades,2 colonnades arrangement structural patterns,in which the space and investment of the 2 colonnades arrangement structural pattern is smallest.When adopting single span arrangement,the frame span is large,the load of the withstanding coal scuttle is large,how to make the structure reasonable and economic becomes the difficulty of the structure plan arrangement.The level beams of the coal scuttle of the side bunker for a 1,000,000 unit uses the concrete truss as the structure plan,the truss has many advantages such as reasonable load transfer,simple connections,light dead weight,the savage of material,higher supporting capacity and so on.The disadvantage of the truss is the weak outside-plane rigidity and it is difficult to resist horizontal seismic force through its own rigidity,so some measurement is needed to solve the problem during the process of the structural arrangement.Compared with the concrete solid abdomen beam,using the concrete truss in the side coal bunker of 1,000 MW unit is beneficial to "strong column weak beam" the conceptual design and has certain superiority to control the top layer displacement,the level relative displacement and so on;the concrete truss plan favors the earthquake resistance compared to the plain concrete frame construction plan so as to provide reference for similar projects.