The Realization Of The Uniaxial Constitutive Model Of Concrete Based On OpenSees

ABSTRACT:Numerical simulation analysis is a main method in studying the seismic behavior of RC structures. The rationality of concrete models is an important factor to affect the results of numerical simulation. Large-scale finite element analysis software OpenSees with object opening become one of the most suitable softwares of nonlinear seismic response analysis because of its strong analysis function and opening characteristic. Since OpenSees software Officially launched,it have been stimulated of many practical engineering and the shaking table test which including reinforced concrete structures, Bridges, geotechnical engineering, proved its good nonlinear numerical simulation precision. Due to the complexity of the concrete material, there are many forms of constitutive model, and there are seven uniaxial concrete models in OpenSees to reflect its mechanical properties.In this article, the seven uniaxial constitutive models of concrete that are included in OpenSees are analyzed and compared comprehensive, it is concluded the characteristics of them.Then, the article introduces the uniaxial constitutive model of concrete that proposed by professor Ding Faxing.It is not only widely used for all kinds of concrete, curve formula is simple, but also needs less parameter.Then, according to the characteristics of the OpenSees, using object-oriented programming method, integrate uniaxial constitutive model of concrete that proposed by Professor Ding Faxing into OpenSees. Finally, use OpenSees to realize the low reversed cyclic loading simulation of concrete column and comcrete beam, also to simulate the frame structure seismic analysis. Mainly use the newly added Concrete08material to realise the finite element analysis of concrete members and structures,then let the results compared with the test results.Verify Concrete08material successfully added and the applicability and convenience of the model.