Finite Element Analysis Of Axial Compressive Properties Of Long Column Of Self-compacting Concrete With Round Hollow Sandwich Steel Tube

Hollow sandwich concrete-filled steel tube(CFDST)is widely used in today’s engineering construction as an efficient structure with low consumption.Most of the previous researches are carried out in the short column,while the research on the long column is relatively less.In view of the present research situation,this paper studies the long column of round hollow sandwich concrete filled steel tube filled with self-compacting concrete.The research is mainly carried out from the following aspects:Numerical simulation method is used to further analyze the axial compression performance of the long column of concrete filled steel tubular(CFST).The most accurate one of the three commonly used constitutive relation models of constrained concrete is selected through comparative analysis.Three groups of friction coefficients were selected for modeling comparison on the basis of experiments and the most appropriate parameters were selected.Using the above parameters to establish the model,the existing test results and simulation results to verify the accuracy of the model;Using the method of single factor analysis,the variation law of the bearing capacity of the long column of concrete filled steel tube subjected to axial force is studied.After the conclusion of the change of the above indexes,the existing formula of axial bearing capacity is revised in the hollow ratio.Compare and evaluate the results of the three methods.By analyzing the known Liu Wei ben structure for circular hollow interlayer simulation effect is good,long concrete filled steel tube column material friction coefficient was 0.6 in the interaction between the simulation effect is best,length-diameter ratio,rate of the hollow main impact on the stability of component lead to bearing capacity,the amplitude of the small influence on bearing capacity of steel tube thickness in obvious,steel tube thickness change outside is large has great influence to the bearing capacity,based on the hollow ratio correction formula are in good agreement with those obtained with the test data.