Experimental Study And Nonlinear Finite Element Analysis On Seismic Behavior Of Reinforced Concrete Pipe Columns With Large Size And Thin Wall

In order to work out the feasibility of Reinforced Concrete Pipe Columns (RCPC) with large size and thin wall(about 40m high, outer diameter is 4m and thickness diameter ratio is about 0.1) applied to air condenser framed structure, four 1/8-scaled reinforced concrete pipe columns were constructed and tested, which put to experiments under repeated horizontal load with constant axial loads.The research mainly includes such contents as below:1. The effects of factors such as axial compression ratio, thickness to diameter ratio and reinforcement ratio on the failure pattern, displacement ductility, rigidity degeneration.2. The feasibility of formula put forward in national code (GB50010-2002)for the design of concrete structure on the annular cross section ultimate load-carrying capacity of RCPC is also analyzed.3. The formula on the shear strength of RCPC has not been found in any national code. How to avoid the failure because of shearing will also been discussed.According to the test phenomena, we can find that the damage mode of all the test specimens is bending failure. The paper proposes that the axial compression ratio play the most important role on the influence of hysteretic characteristics and displacement ductility from the analysis of the tests data. The higher the ratio of axial compression is, the worse the seismic behavior is. With the increase of thickness to diameter or reinforcement ratio, the seismic behavior of the test specimens become better. At the same time, the formula suggested by national code(GB50010-2002) is suitable for those large size-thin wall annular cross section. At last, It is recommended some methods for the design of RCPC applied to air condenser framed structure.In the last two chapters of this paper, the crack development, load-displacement curves and the working state of all the materials are simulated by ANSYS software indetail, and the analysis result results keep good pace with the experimental results. The nonlinear theoretical analysis is carried out, which can been a basis for further research.