Experimental Research On Bond Strengh Properties Between Rubberized Concrete And Steel Bars

Rubberized concrete is a new type of concrete material that rubber is put into ordinary concrete.Research shows that rubberized concrete has the advantages of low modulus of elasticity;large damping and so on,good toughness,crack resistance,impact resistance and abrasion resistance,but rubber will reduce the strength of concrete.Surface treatment of rubber particles can enhance bond between rubber and concrete and improve strength of rubberized concrete.In order to obtain the bond strength between steel and rubberized concrete and promote the application of rubberized concrete in engineering,This paper studies the amount of rubber(replace the fine aggregate by same volume: 0%,10%,15%),size of rubber particles(1 ~ 3 mm,3 ~ 6 mm),diameter and shape of steel bar,surface treatments of rubber particles(not processing,water,1% NaOH aqueous solution,1% NaOH aqueous solution and KH570 compound treatment)influence on bond strength properties between steel bars and rubberized concrete.The main contents include:1、The effects of the amount of rubber,size of rubber particles and surface treatment of rubber particles on the compressive strength and splitting tensile strength of rubberized concrete were studied by the compression strength and splitting tensile strength test of 102 cube specimens with the size of 150 mm × 150 mm × 150 mm.The results show that the compressive strength of rubberized concrete is linearly related to the splitting tensile strength in a certain strength range(C20 ~ C40).The compressive strength and the splitting tensile strength decrease with the increase of the amount of rubber,and increase slightly with the increase of the size of rubber particles.The effect of water washing and 1% NaOH aqueous solution on the compressive strength and splitting tensile strength of rubber concrete is not significant,and the effect of compound treatment is more remarkable.2、The effects of the amount of rubber,size of rubber particle,diameter and shape of steel bar,surface treatment of rubber particles and so on bond Strength properties between steel bars and rubberized concrete were studied by the center pull-out test of 1020 cube drawing specimens with the size of 150 mm × l50 mm × 150 mm.The results show that the bond strength decreases with the increase of the amount of rubber.The increase of rubber content is nonlinear with the decrease of bond strength.The bond strength of 3 ~ 6 mm is about 1.03 times of 1 ~ 3 mm.With the increase of diameter of deformed steel bar,the bond strength increases first and then decreases.The bond strength increases with the increase of diameter of plain bar.The effect of water treatment and 1% NaOH on the bond strength is not significant,but the effect of compound treatment on the bond strength was significant,and the increase effect was weakened with the increase of steel bar diameter.The average reinforcement of the deformed steel is 10.65%,and the average reinforcement of the plain steel bar is 12%.The bond strength of the plain steel bar and rubberized concrete is about 0.46 times of that of the deformed steel bar.3、The influence of amount of rubber,size of rubber particle and surface treatment of rubber particles on the displacement was studied.The results show that the displacement increases with the increase of rubber content.There is no obvious regularity between the displacement and the size of rubber particle.Three surface treatments of rubber particles reduce the displacement of deformed bar and rubberized concrete,but increase for plain bar.The displacement of plain steel is smaller than that of the deformed steel bar with the same diameter of bar.4、The calculation model of the ultimate bond strength of deformed bar and rubberized concrete is obtained through the statistical regression of this experiment and related research data.