Finite Element Analysis on Axial Bearing Capacity of Square Double Skin Steel Stub Short Columns Filled with Recycled Concrete

Based on the compressive strength experiment of vitrified micro bubbles (VMB) recycled concrete double mixed diatomite calcined and fly ash, this paper adopts the finite element software ANSYS to analyze the impacts of different hollow ratio and VMB content on axial bearing capacity of square double skin steel stub short columns filled with recycled concrete in condition of 100% recycled coarse aggregate replacement ratio and 3% diatomite calcined content. The result shows that: Compressive strength of VMB recycled concrete increases with the increase of diatomite calcined content from 0 to 3%, when the content of diatomite calcined is 3%, compressive strength of the 130% VMB content test specimen can reach 32.45 MPa; When the hollow components reach ultimate bearing capacity, their axial displacement decrease by 5.6% compared to solid components, improving buckling capacity and ductility of components; When the VMB content is same, ultimate bearing capacity of hollow components compared to solid components increase by 2.5%; When the hollow ratio is same, ultimate bearing capacity of the 130% VMB content component compared with 0% content component only reduces by 3.5%; By means of the regression analysis of the component axial pressure data, we have exported bearing capacity of square double skin steel stub short columns filled with recycled concrete under axial compression.