极端严寒天气降温工况污泥浓缩池有限元分析

Finite Element Analysis of Sludge Thickening Tank Considering Rapid Temperature Drop

为准确模拟圆形水池的受力特性,采用有限元软件中实体单元对某工程中污泥浓缩池进行建模,通过对其分析结果中弯矩及轴力计算值与计算手册静力计算表计算值进行对比,验证了模型有限元计算结果的准确性。据此建立实际工程有限元模型,并同时考虑低温环境下的水池内外温差进行分析,对本工程分析结果表明:采用实体单元能够较好模拟水池的力学性能,混凝土及钢筋的应力分布及温度应力形成的裂缝也能得到良好的体现;仅考虑满水工况下,钢筋与混凝土的应力处于较低水平;在考虑降温工况与静水压力共同作用的情况下,水池截面的竖向弯矩与环向轴力均有大幅度增长;带有附件的水池(连续走道板、挑檐、水槽等)建议采用较为精细的有限元建模。圆形混凝土水池设计中应采用加以考虑季节温差、极端天气下壁面温差的结构设计方法。

To simulate the mechanical characteristics of a circular pool,solid elements in finite element software were adopted to model a sludge thickening pool in a finished project.The bending moment and axial force in the analysis results were compared with the values calculated by design manual,and the accuracy of the constructed model was verified.,A coupled analysis was performed to the constructed model considering the temperature difference between inside and outside surface of the pool.The analysis results show that the constructed model based on the solid elements can simulate the mechanical property of the pool accurately,in which the stress distribution of concrete and steel bars and the temperature cracks can be described with certain accuracy.The stress state is at a low level under the full water condition only,but the vertical bending moment and the circumferential axial force of the cross section increased greatly considering the cooling condition and hydrostatic pressure together.Detailed finite element model is suggested to simulate the pools with accessories,such as continuous walkway plate,pick eaves,sink,etc..The temperature differences among seasons and those between the wall surfaces under extreme weather condition should be considered in the structural design of circular concrete pool.