Evaluation Of The Stability Bearing Capacity Of The Arch Structure Based On Elastic Modulus Reduction Method

The arch structure not only meets the practical requirements of people's lives,but also has high ornamental value.It has been widely used in the field of civil engineering.For the ultimate bearing capacity analysis of engineering structures,the elastic modulus reduction method(EMRM)has good computational efficiency,accuracy and stability.Therefore,this paper studies the stability bearing capacity of arch structure based on EMRM.The main work and results as follows.(1)Study on the bearing capacity of circular section concrete filled steel tube(CFST).Through collecting and setting up test database including 531 axial loaded members,94 pure bending members and 384 compression-bending members,and accordingly compared the bearing capacity equation of the precision and applicability of four foreign codes,two domestic codes and a CFST monograph,it lastly determined by bearing capacity equation of Zhong Shantong(2006)monograph to calculate the bearing capacity of circular CFST.(2)The stable homogeneous generalized yield function(HGYF)of I-section steel members and circular CFST members with wide applicability are established.Firstly,the generalized yield function(GYF)is established by using the bearing capacity equation of the I-section steel members and the circular CFST members.Considering the influence of the stability factors,the homogeneous GYF strategy is established for the uncertain parameters,and to establish the broad applicability of the HGYF of the I-section steel members and circular CFST members,which can effectively overcome the problems of GYF stability and poor accuracy,and avoid the traditional homogeneous strategy which need the undetermined parameters GYF regression analysis to carry out repeated.(3)EMRM for evaluating of the stability bearing capacity of I-section steel arch is established.It can set up I-section steel arch finite element calculation model based on linear elastic beam element,and combined with the EMRM to calculate arch steel structure stability capacity,finally compared with the test results and the results of numerical methods,which show that the proposed method has high accuracy and efficiency.Besides,the stable HGYF should be used to calculate the stability bearing capacity of I-section steel arch.(4)EMRM for evaluating of the stability bearing capacity of the circular section CFST arch bridge with circular section is established.Firstly,by introducing the theory of CFST,a finite element model of CFST arch bridge is established by using the linear elastic beam element.And then combined with EMRM to calculate CFST arch bridge stability bearing capacity,compared to the difference between stress and strength stability bearing capacity,discussed the different stability coefficient and stable HGYF on the calculation result,and then compared with the test results and the results of incremental nonlinear finite element method(INFEM),which show that the proposed method has high accuracy and efficiency and overcome the drawbacks of INFEM.Finally,the effect of span ratio,slenderness ratio,steel ratio,concrete strength and loading mode on the bearing capacity of the circular section CFST arch is studied,which can provides reference for structural design and analysis.