Nonlinear Finite Element Analysis On Box Reinforced Concrete Inverted Siphon

The South-to-North Water Diversion is a major strategic project for ease the acute shortage of water resources in northern China. It alleviate the acute shortage of water resources in northern and promote north and south economic, social and population, resources and environment coordination development through the rational allocation of inter-basin water resources. The inverted-siphon of the Project of Middle Route of South-to-North Water Diversion is divided into two types, one inverted-siphon is used when the channel through the valley, which is a major, and another is used when the river through the channel. Large flow, large sizes of structure, heavy load are its salient features. The safe operation of its ability directly determines whether the Project of Middle Route of South-to-North Water Diversion plays its role and effectiveness. Therefore, to understand the stress state of inverted-siphon structure under different conditions is necessary. Particularly when the material nonlinearity of structure was taken into account, the stress, strain and displacement of inverted-siphon is worthy to further study.In this paper, use the finite element analysis software ANSYS as a platform, nonlinear finite element analysis on inverted-siphon which is under five kinds of loading conditions and soil which is under two kinds of loading conditions. When analysis the inverted-siphon, Solid65 element was selected to establish reinforced concrete models and Solid45 element was selected to establish soil models according to non-linear elasticity theory. Plane42 element was selected when analysis the soil to establish models according to elastic-plastic theory. Integrated model was selected to simulate steel bar in the inverted-siphon. Stress field and displacement field was extracted. The results showed that side wall and axillaries angle of inverted-siphon usually under high stress, it should be enhance them. Meanwhile, seam wall usually under low stress, it could be considered to reduce the size or reinforcement ratio of the wall. The results also showed that the likely location of cracks. The results of soil analysis showed that it does not have large deformation. About 50mm subsidence occurred in the foundation of the inverted-siphon, which accord with the relevant technical requirements. And it showed that bearing capacity of foundation under inverted-siphon can meet the engineering needs.Through the simulation of different loading conditions, obtained the stress and displacement values of inverted-siphon and soil. After comparative analysis, it provides a visual and quantifiable reference for similar projects design.