Nonlinear Finite Element Analysis On Super-High-Strength Concrete Columns In Mechanics Performance

Recently,super-high-strength concret (SHSC) is more and more widely used because of its good capability of resisting architectur needs of high-rise structure. SHSC has been shown to have advantages such as higher strength and better durability. And nonlinear finite elemen tmethod means a great progress for RC structure analysis. This method makes it possible for investigators to simulate the whole proeess of RC structure, the material characteristic of RC such as elasticity, plastieity and erack and the bond between conerete and steel. The property of RC structure can be grasped more deeply and fully by calculation.In the paper,the author firstly begin with the Strain-Stress relationship of RC materials, the Failure Criteria, Failure Surface and various Failure Model of concrete is discussed respectively. Seeondly, all element types needed in Nonlinear Finite Element Analysis (NFEA) of RC structure and the compounding models in ANSYS are studied.Based on the low-cycle reversed loading tests , the super-high-strength concrete columns of different shear span ratio and different stirrup reinforcement ratio were modeled with ANSYS software and the low-cycle reversed loading tests on condition of different axial load ratio were non-linearly simulated. The hysteretic curves,skeleton curves were obtained. The calculated hysteretic curves and skeleton curves were corresponding well with experimental results. Through the fitting analysis of the data, we can test the variance relationship between the energy-dissipatio the axial load ratio and the stirrup reinforcement ratio of concrete columns more clearly. The data reflect the seismic performance rule of the super-high-strength concrete columns under earthquake load. Then the paper make supplement and further discussion using the finite element analysis results, bring out an improved formula to ameliorate the former supplemental normative super-high-strength concret columns diagonal-section shear strength. Through the calculation, the author find that the improved formula has an better accuracy and less discreteness.