Expermental Study On Mechnical Behavior Of Highperformance Iron Tailing Concrete Columus

In recent years,urbanization in China is growing quickly,the surge in concrete consumption has led to plummeting resources in many areas,particularly in natural sand resources supply and demand in tension.The rapid increase of reserves of iron tailings resources in China has brought about great harm to the ecological environment.This paper studied a kind of high performance iron tailings concrete,in order to reduce the pressure on the supply of natural sand resources,and used of industrial waste—iron ore tailings and iron tailings powder to the maximum extent.This paper explored the mix proportion design schemes of the concrete to find out the best mix,and then based on this kind of high performance iron tailing concrete as raw material to make compression members of the high performance iron tailings concrete.The work of material mix included:(1)This paper studied the water cement ratio,the sand cement ratio on the effect of the concrete cube compression strength of 7 days and 28 days and the flow expansion degree of concrete and the time of 500 mm as the first group,combined with the principle of maximizing the use of waste,found the best ratio of the water cement ratio and the sand cement ratio.(2)The second group adopted the best water binder ratio and sand binder ratio of the first group with the different proportion of fly ash instead of cement and iron tailings powder in different proportions to replace silica fume,and studied the effect of the two factors to the concrete cube compression strength of 7 days and 28 days and the flow expansion degree of concrete and the time of 500 mm,combined with the principle of maximizing the use of waste,found the optimal replacement ratio.The work of compression members mainly included:(1)The axially compression members of high performance concrete of iron tailings for the same material,the same section size,the same reinforcement scheme,was tested on the experimental study of the axial compression.The failure characteristics was observed,and the ultimate bearing capacity,concrete strain,steel bar strain and the middle part of the component was measured.(2)Ultimate bearing capacity and deflection of the middle member of the column of high performance iron tailings concrete,based on control variable with different eccentricity,were studied.(3)This paper analyzed the break section of the column of the high performance tailings concrete from the beginning of loading to the ultimate bearing capacity.The experimental data was analyzed to conclude the effect of the long and thin ratio and initial eccentricity of high performance iron tailing concrete column to cracking load and bearing capacity.The formula of bearing capacity of this concrete under axial and eccentric compression was proposed.The research of the test performance of this new type of iron tailings concrete material lays a certain foundation for the follow-up study.The Mechanical performance of members was tested,and has provided a reference for the practical engineering application of this kind of iron tailing concrete.