Stress Analysis On Thick-walled Cylinder Of Multilayer Concrete Material With Functionally Graded Characteristics

Thick-walled cylinder of concrete material is an important supporting structure, which is widely applied in many fields, such as hydropower, mine, and chemical industry. In order to improve the elastic ultimate bearing capacity of the thick-walled cylinder, generally, we could increase the thickness of cylinder wall, enhance the strength of materials and so on. However, the theory and engineering practices show that, it is hard to significantly improve the elastic ultimate bearing capacity of the thick-walled cylinder when the cylinder is thick enough. Meanwhile, the project cost is increased because the material far away from the hole-edge has not been fully utilized.For non-homogeneous functionally graded material, we may enhance the elastic ultimate bearing capacity of the thick-walled cylinder significantly by continuously changing of material composition along the radial direction and increasing the wall thickness. In this paper, the ideology of Functionally Graded Material (FGM) is introduced. Through stratifying or partitioning the thick-walled cylindrical, we apply the concrete materials of different elasticity modulus in different layers or regions to simulate the FGM, so as to flat the stress distribution, reduce the stress concentration, enhance the elastic ultimate bearing capacity of the supporting structure, reduce the amount of excavation and save project costs.