Behavior Of Recycled Large Aggregate Concrete Filled Steel-tube Subjected To Compressive Loading And Bond-slip

Recycled concrete filled steel pipe is to point to regenerate dissipate concrete, and fill itto the steel pipe to form the component. Following with the growth need of the more concretearchitecture, at the same time increase the pollution of the environment by discard concrete.The cost of the deal with these waste concrete is terrible. So it had a huge impact on socialand environmental. In addition, due to deficit of natural energy now and state environmentalprotection policy of open source throttling, so much attention has been paid to recycling ofwaste concrete has become an important topic in the academic discussion. However, as aresult of the recovery process recycled aggregate is more complex, and the expense is tooheavy, so we will make of recycled aggregates of simple processing before waste concrete andthe aggregate used in concrete. The recycled aggregates exist crack, high defect rate of waterabsorption, and its mechanical properties is limited. if the recycled aggregate concrete filledsteel tube, the binding effect of the tube to the core concrete, and form recycled aggregateconcrete, its mechanical properties will be greatly improved, so establishing the concept ofsteel recycled aggregates concrete.Using replace rate, aggregate size and member slenderness ratio as the importantparameters of recycled large aggregate concrete with steel-pipe, to make different shortcolumn. And discuss on deed of dissipate large aggregate concrete filled steel-tube beared topressure loading and bond-slip. And the below field has some complications:1. Replace rate of recycled aggregates (η), recycled aggregate size (a) as the mainparameters of recycled aggregate concrete to conduct9groups of54prism axial compressiontest, and analyse the experimentation record. Thus, in order to get the best of recycledaggregates instead of elastic modulus ratio and the optimal particle size and recycledaggregate concrete.2. Replace rate of recycled aggregates (η), revive aggregate size (a) of slenderness ratioand component () by way of the principal element, to conduct12pieces of steel recycledaggregate concrete axial compressive test on performance and record the experimentphenomena and test data. Through the trial phenomena to analyse the affect of recycledaggregate permute percentage, grain size and slenderness ratio on the recycled aggregateconcrete filled steel pipe members with buckling strength and the ultimate strength.3. The steel tube recycled aggregate concrete numerical simulation by finite elementanalysis to use the modulus of elasticity constitutive relation and recycled aggregate concretein the test. By using the finite element software separately from the constitutive nexus of material pattern, unit style selection, reseau slicing, steel and concrete interface mould,boundary requirement, considering welding residual stress6aspects force and nonlinearequation solving method to establish model and simulate the whole course of axialcompression stress. And compare the calculated results with test outcome to verify theaccuracy of test results.4. Through replace rate of recycled aggregates (η), and the interface bonding length (L)as the main parameters to conduct the steel tube recycled aggregates concrete of bond slip test,and record the experiment appearance and test information. Through the experimentalphenomena and data to analy the influence of recycled aggregate replacement rate andbonding interface length on the large aggregate concrete steel tube with ultimate bondstrength and initial strength. And analy loading end, middle and end of pipe load of relativeslippage steel with pipe and the recycled aggregates.