Flexural Behavior Of Stainless Steel-concrete-steel Concrete Filled Double Skin Steel Tube

Stainless steel-concrete-steel concrete filled double skin steel tube is a kindof new constructional element based on the traditional concrete filled doubleskin steel tube. This kind of constructional element inherits the merits such ashigh bearing capacity, high plasticity, high toughness, high fire resisitance, highflexural stiffness, light weight,etc. Besides, it has the advantages of goodcorrosion resistance and durability as a result of the stainless outside-steel tubematerial.This paper has done a systematic study both on the testing analysis andthe finite element simulation on the flexural strength of stainlesssteel-concrete-steel concrete filled double skin steel tube.With the result ofparameter analysis a new caculation method has been purposed to caculate theflexural capacity of stainless steel-concrete-steel concrete filled double skin steeltube.In this paper, the main research contents are as follows:(1) With the change of shear span ratio and hollow ratio carried out a seriesof bending test. Using the data acquisition system recorded the data of load ofstress, displacement, strain changes in whole process.The result show that: stainless steel-concrete-steel concrete filled double skin steel tube specimensunder pure bending load performance for ductility damage. The greater shearspan ratio, the lower flexural bearing capacity; When its hollow ratio not greaterthan0.70, with the increase of the specimen hollow ratio,its flexural bearingcapacity is improved; When the hollow ratio is greater than0.7, with theincrease of specimen hollow ratio,its bending strength is decreased.(2) Using ABAQUS to caculate the bending capacity of stainlesssteel-concrete-steel concrete filled double skin steel tube, the finite elementcaculation results are good agreement with the test results. All specimens’ultimate flexural bearing capacity’s test results and the finite element result’sratio is equal to0.986, Its standard deviations is equal to0.083, namely thedeviation of finite element analysis’ results with the test results of is small andthe discrete data is not obvious.(3) Using the finite element software after it verified to analyze thespecimens’ bending process, get the outer steel tube,inner steel tube, concrete’sstress distribution and get the works of stainless steel-concrete-steel concretefilled double skin steel tube under pure bending load.(4) With the variation of shear span ratio, hollow ratio, concrete strength,the nominal inside diameter thickness and radius-thickness ratio, usingorthogonal experimental design principles to design orthogonal test, using thefinite element modle to analyse the tests’ result of the orthogonal table,analysis of variance were applede to analyze the result of orthogonal test’s result, getevery factors’ influence to specimens’ flexural behavior.(5) Analysising the factors which affect the specimens’ ultimate flexuralcapacity, on the basis of parameter analysis,a new caculation method has beenpurposed to caculate the flexural capacity of stainless steel-concrete-steelconcrete filled double skin steel tube.