大型地上实验水池钢结构方案研究及计算

STUDY AND CALCULATION OF STEEL STRUCTURE SCHEMES FOR A LARGE EXPERIMENTAL TANK ABOVE GROUND

针对某建造于地面上储水量达22500 t的大型钢结构水池,提出了多种结构方案。通过多方案的分析比较,确定了水池钢结构方案:主体结构由梯形截面桁架立柱、多道水平腰桁架以及多道封顶桁架组成;池壁采用连续支承的弧形钢板形成张力结构,能有效抵抗静水压力作用,降低钢板厚度;施工过程采用先安装梯形桁架立柱,然后在桁架立柱顶部施加对拉预应力并临时锚固拉索,之后安装水平腰桁架和封顶桁架,最后卸掉拉索并安装弧形壁板。这种无索预应力方案,使得结构安装后桁架立柱的锁定内力能与静水压力作用产生的弯矩相互抵消,极大地降低了正常使用的应力水平。在此基础上,研究了整体钢结构水池的动力特性以及主要工艺荷载效应(造浪、物体高速入水)等;建立了钢结构水池的流固耦合分析模型,研究了地震动时程响应。最后,给出了池壁观测开洞方案及数值分析结果、地基基础设计方案等。

Being aimed at a requirement to construct a large steel water tank containing 22500 tons above ground,Sereral schemes were proposed.Through the analysis and comparisons of multiple schemes,the steel structure scheme of the tank was determined:the main structure was composed of trapezoidal cross section truss columns,multiple horizontal waist trusses and multiple capping trusses.The wall of the tank was made of continuous supporting arc-shaped steel plate to form a tension structure,which could effectively resist the effect of hydrostatic pressure and reduce the thickness of the steel plate.During the construction process,the trapezoidal cross section truss columns were first installed,then pre-tension was applied on the top of the truss columns and the cables were temporarily anchored,after that the horizontal waist trusses and capping trusses were installed,and finally the cables were removed and the curved wall plates were installed.This cable-free prestress scheme could make the internal force of the truss columns after the structure installed and the bending moment generated by the hydrostatic pressure cancel each other out,greatly reducing the stress level of the steel structure in normal use.On this basis,the dynamic characteristics of the overall steel structure tank and the main process load effects(wave-making,high-speed entry),etc.were studied.Based on a fluid-structure coupling analysis model of the tank,the time-history response of the seismic motion was studied.Finally,the hole opening scheme for the wall plate and numerical analysis results,as well as the design scheme of the foundation were given.