| This article is from the protection environment, the conservation of resources, reduce the discharge solid waste and angle, in view of the problem of abandoned concrete component reuse, South China University of Technology in the preliminary research steel tube regeneration mixed component, and on the basis of this paper abandoned concrete component reuse and thin square steel tube wall set longitudinal stiffening rib, improve the critical buckling happened steel plate stress, the stress distribution is more uniformly delaying wall on the issue of local buckling is discussed, and both seek a balance point, for not ribbed and ribbed steel thin-walled square block mixed short column regeneration of the axial compression performance, and carry out the following preliminary work:(1) Through the15square block thin-walled steel pipe regeneration of mixed short columns axial compression test, the result shows that the main failure form for specimens YaoGu form pressure knit damage, individual specimens have occurred in the trend of the shear damage, this basically is concrete combination of old and new layer place strength of concrete and the regeneration of block contains size uneven pebbles to aggregate specimens of mechanical properties and has a great influence on the damage form; The steel tube specimen in elastic state, each face stress is evener, section and each corner of strain growth even change, into the elastic-plastic state, specimens strain of core concrete by damage or shear failure surface location much effect; According to the test failure mode and combination layer core concrete destruction analysis results, establish the thin-wall square steel tube regeneration block mixed short column by steel tube of local buckling and combination layer core concrete destruction caused by the YaoGu form pressure knit damage theory model; Load-deformation in the destruction of the decline period stage, not ribbed specimen showed softening phenomenon, ribbed specimen showed obvious stiffener characteristics that have good carrying capacity and resistance to deformation ability; Don’t ribbed axial compressive specimens of bearing capacity increase coefficient are generous with SI section than and set of hoop coefficient and the increase of first increases, then decreases, this is because not ribbed short column in the pipe of generous than the limit, B/t than72; Ribbed specimen SI with generous than B respectively section/t and decreases, set of hoopζcoefficient increases while, this is because ribbed short column son of the panel is generous than meet the requirements; Ribbed specimens ductility coefficient DI than not ribbed specimens are too large, an average of ductility coefficient of53.75%.(2)The effective method of thin-walled steel tube width consider local buckling of ultimate bearing capacity of the adverse impact of, through the test data regression, draw not ribbed and ribbed steel thin-walled square block mixed short column regeneration of concrete improve coefficient and set of hoop coefficient linear relationship between the basic, and introduction of this paper not ribbed and ribbed steel thin-walled square block mixed short column regeneration of the axial compression bearing capacity expression, and can predict the thin-walled steel this square regeneration block mixed short column axial compression bearing capacity of the components, and relevant literature and procedures, the formula analysis, high precision, and can provide reference for the engineering practice.(3) Using finite element software to ANSYS10.0specimens for nonlinear finite element analysis, the paper is concerned, the deformation and stress and strain of internal concrete cracking analysis, obtains ribbed thin-wall square of the concrete filled steel tube stress mechanism; ANSYS analysis reaction of concrete crack development form basic response specimen fracture development situation, and test YaoGu happen knit the damage form pressure crack distribution, consistent. |
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