| The wind turbine is mainly subjected to the horizontal wind load,which produces a great bending moment to the connection of foundation and embedded ring.The bending moment is transmitted to the foundation through the embedded ring connection,therefore the connection is very important for the safety of the wind turbine.It is of great significance to study on bending bearing behavior of wind turbine foundation and embedded ring connection.The main results of this paper are as follows:Firstly,in this paper,four model specimens are designed,and the horizontal low-cycle cyclic loading is applied to the top of the steel cylinder.The influences of the burial depth,the width of the lower flange,and the steel bar of the embedded ring are studied.As the load increases,the displacement between the steel cylinder and the concrete increases gradually,and the cracks around the steel cylinder gradually expands.The ultimate failure of foundation concrete is manifested as the dominant crack in the loading direction and the oblique 45 degree direction.The depth of embedded ring and the width of lower flange have great influence on the ultimate bearing capacity of foundation and embedded ring connection.The contribution of the steel bar of the embedded ring to the ultimate bearing capacity of the connection is not significant,and it can improve the ductility and deformation capacity of the connection as the structural reinforcement connecting the inner and outer concrete of the embedded ring.Secondly,using ABAQUS finite element analysis software,the three-dimensional finite element model of the test specimens are established based on the damage plasticity constitutive model of concrete.The results of numerical simulation are in good agreement with the experimental results.The results are as follows:The concrete near the lower flange of the embedded ring is the most prone to stress concentration,where the damage is the most serious;With the increase of load,the damage of foundation concrete gradually spreads from the concrete near the lower flange to the upper part,and the concrete surface also has obvious damage;The stress around the lower flange has a certain distribution along the circumference.Finally,a simplified design method for bending moment capacity of foundation and embedded ring connection is proposed.Combined with engineering examples,the bending bearing capacity of embedded ring connection is re-checked and the design parameters of connection are improved.The research results can be used for reference to master the bending bearing capacity of the foundation and embedded ring connection and to improve the design method of the embedded ring. |
