Experimental Study On Mechanical Properties Of Steel Fiber Reinforced High Strength Concrete And The Shaft Lining Research

With the continuous development of coal resources,Nii construction of the vertical shaft through the water will become more and more thick alluvium and the sidewall of the external load will also be increased.In order to resist the strong external load,it is necessary to adopt high strength shaft lining structure.The use of high-strength concrete is the most effective way to improve the bearing capacity of the shaft lining,but with the increase of concrete strength grade,the brittleness of concrete increases obviously,and the structural failure becomes sudden.In order to solve the problem of water bearing instability in the wellbore and to improve the brittleness of high strength concrete,the steel fiber reinforced high-strength concrete was used as the wall material,and the mechanical properties and the wall structure were studied.Firstly the main influencing factors of enhancing effect and failure mechanism and the enhancing effect of steel fiber on concrete were analyzed.The concrete lining of steel fiber reinforced high strength test and the basis mechanical performance test were designed to get the uniaxial compressive strength,high strength steel fiber reinforced concrete splitting tensile,elastic modulus and the stress-strain relationship,three axial compressive mechanical index;then,carry out the model test of steel fiber reinforced concrete lining structure of high strength were carried out to get the shaft lining structure stress,deformation and strength characteristics;finally,through the ABAQUS software,the analysis models of the lining structure were established and the wall structure is simulated and analyzed.According to the calculation results,the bearing capacity calculation formula of shaft lining is obtained by regression.The results of this study show that the steel fiber can effectively prevent the development of macro cracks and the brittleness of steel fiber reinforced high-strength concrete is improved obviously.The reinforced steel fiber reinforced high-strength concrete shaft lining structure is superior to the reinforced high strength concrete shaft lining structure in the ultimate bearing capacity and mechanical characteristics,and can improve the reliability of engineering wall structure,which is an ideal high strength shaft lining structure.