Research And Development Of Conductive Epoxy Resin Concrete And Conductive Properties

This paper discusses the influence of materials on the production process and strength and electrical conductivity of conductive epoxy resin concrete;studies the effects of electrode form,electrode material and preparation process on strength and conductivity;through the conductive admixture of the type and dosage test,seek the best conductive external admixture;studies the influence of aggregate content on the strength and electrical resistance of conductive epoxy resin concrete was studied,and discusses the mechanism;chooses the best diluent type and dosage from The representative two diluents(acetone,691).Through the resin concrete immersion test,test the moisture content and resistance variation law;resin concrete temperature testing,analysis resistance variation in the temperature effect.Based on the experimental data and the current theoretical research,studies the seepage theory of conductive epoxy resin concrete and determines the threshold value of seepage;analysis of conductivity of conductive materials with low content in combination with experimental data,discusses the tunneling conductive mechanism;based on the experimental data,puts forward a spindle-shaped microstructure model.The following major results were achieved:1)In the electrode form and the preparation process,the steel mesh electrode is the better electrode form,the dry mixing method is superior to the external mixing material wet mixing method and the aggregate wet mixing method.The optimum formula of conductive epoxy resin concrete is:Epoxy resin:curing agent:thinner 691:graphite powder:the sand = 1:0.4:0.2:1:3.2)The influence of humid environment on the electrical conductivity of conductive epoxy resin concrete is negligible;the electrical resistance of conductive epoxy concrete is positively correlated with temperature,and the temperature coefficient is about 3×1O-3/℃,and the temperature creep phenomenon exists;with the increase of the load,the resistance change of the test piece is divided into three stages:the pre-resistance continues to decrease,the medium-term resistance is basically stable,and the terminal resistance increases sharply.3)The conductivity mechanism of conductive epoxy resin concrete with seepage effect and tunneling effect is proposed:the amount of conductive material is less than the threshold value,the tunnel effect is dominant;the volume fraction of conductive material is close to the threshold value of seepage,the theory of percolation and tunneling effect;the seepage theory is the dominant factor.4)The microstructural model of the conductive epoxy resin concrete is proposed.The conductive sand is connected by conductive chains.As the sand content increases,the conductive chains become thinner until the coating layer contacts.