Experimental study on curing index of adhesives for retard-bonded prestressed steel strand
In recent years,the retard-bonded pre-stressed technology has become popular in the pre-stressed structures thanks to its excellent characteristics.The key material for the retard-bonded pre-stressed technology is the retard-bonded pre-stressed steel strand,and the technical principle is to bond the steel strand with the surrounding concrete through an adhesive solidified in the steel strand.Therefore,the bonding and anchoring properties of the structure are improved.At present,there are few researches on the curing evaluation index of the adhesive in academic and engineering circles.In this paper,four common curing indexes of the cured adhesives were studied,including shore hardness,tensile shear strength,compressive strength,and bending strength.The results indicated that the corresponding curing time was close to each other when the four curing indexes of the adhesive reached maximum,indicating that the four curing indexes were consistent.The maximum values of shore hardness exhibited the smallest dispersion coefficient of 0.013,and the charac-teristic value at a shore hardness of 80 D presented the best curing evaluation index for the complete curing of adhesives.
retard-bonded prestressed technologyadhesiveshore hardnesstensile shear strengthcompressive strengthbending strengthcuring index