Research On Bearing Behavior Of Demolished Concrete Blocks Filled Thin-walled Square Steel Tubular Long Columns Under Axial Compression

With the rapid advance of our urbanization and the continuous of urbanrenewal, Construction waste that generated each year produces a tremendous burdento the urban environment and land resources, How to reasonable reuse wasteconcrete has become one of the current research hot topic. So introduce a relevantresearch that Recycled-concrete-Blocks Filled Square Steel Tubular Columns.Selecting a particle size of approximately80-150mm from simple crushed wasteconcrete to replace ordinary aggregate partially while producing concrete asdemolished concrete blocks，then combine with the thin-walled steel tube, this issteel tube column filled with demolished concrete blocks. In this paper, through thenumerical simulation analysis and experimental research of thin-walled square steeltube regenerative mixed concrete long columns of axial compression bearingcapacity is studied.With the aid of finite element analysis software Ansys, Analysised the BearingCapacity of Recycled-concrete-lump Filled Square Steel Tubular Long Columnsunder Axial Compression by selecting the slenderness ratio, steel ratio and mixingratio parameters. Load-displacement curves was obtained from the analysis. Theresults of study show that the Recycled-concrete-lump replacement percentage hasunconspicuous influence on the specimens bearing capacity，which is in inverseproportion to the slenderness ratio and in direct proportion to the steel ratio.With slenderness ratio and mixing ratio as variable parameters, inspected thebearing capacity under axial compression though ten Thin-walled square steel tube.The results of study show that:(1) Load-axial displacement curves was consists ofelastic stage, elastic-plastic stage and plastic stage, At the beginning of the load, thesteel tube and core concrete bear loads respectively, load-axial displacement curve islinear nearly;(2) Early loading, the Mid span-section of components accord withflat section assumption mainly;(3) The influence on the ultimate bearing capacity ofslenderness ratio associated with the actual failure mode closely, mixing ratio andslenderness ratio did not significantly affect the ductility factor of the components. The experimental results of bearing capacity were in comparison withcalculation according to domestic and foreign relevant codes, the standardDBJ13-51、CECS159and AIJ are in good agreement with the test results, but thereare large discreteness on the calculation of DBJ13-51and AIJ, recommendingprocedures CECS159when Calculate the bearing capacity. The formula forcalculating the ultimate bearing capacity of Recycled-concrete-lump Filled SquareSteel Tubular Long Columns under Axial Compression was obtained in the endthough the experimental results.