| Reactive Powder Concrete(RPC)is a new type of cement-based composite material which has the advantages of super high compressive strength,high tensile strength and good substitution.Combining excellent performance RPC and profile steel to form steel reinforced RPC(SRRPC)combined structure,can not only significantly improve the bearing capacity and seismic performance of components,but also can improve the component’s service life by virtue of RPC’s good durability.And it is suitable for tunnels,oceans and other environmentally erosive engineering fields,and has good application prospects.At present,there is still little research on the new composite structure at home and abroad.In order to explore the feasibility and superiority of the SRRPC composite structure in actual engineering,to solve related technical problems,and to eliminate the effect of the size effect on the mechanical performance of the structure,this paper conducted the large bias performance test of SRRPC full scale column,mainly completed the following work:(1)Based on eccentricity and steel sintering test parameters,six SRRPC full-scale columns with a cross-section size of 300 mm × 350 mm and a height of 3000 mm were designed to carry out large load bearing capacity tests.Obtain the ultimate bearing capacity,lateral deflection and section strain.The test results show that the composite structure has high bearing capacity.The ultimate bearing capacity of a column increases with increasing steel content and decreases with increasing eccentricity.(2)Non-linear simulation analysis of 6 SRRPC full-scale column specimens with ANSYS finite element software was performed to obtain the lateral flexural deformation,ultimate bearing capacity,and stress contour maps of steel and RPC.The calculation results agree well with the test results.Twenty-five specimens were calculated using the same modeling method,and the parameters were extended to further analyze the effects of eccentricity and steel content on the maximum lateral deflection and ultimate bearing capacity.(3)The deflection second-order effect of SRRPC specimens is studied and analyzed.Based on the results of experiments and finite element calculations,and considering the influence of steel content,and using the "critical curvature" analysis method,a calculation formula for the second-order effect of SRRPC large eccentric compression columns was established.(4)Based on the test phenomena and results,the basic assumptions for bearing capacity calculation of SRRPC large eccentric compression columns are proposed.Based on the assumption of the flat section and considering the contribution of the RPC tensile stress in the tensile zone of the section,a calculation formula for the ultimate bearing capacity of the SRRPC column was established,which can be used for reference in engineering design. |
