Experimental research on direct shear behavior of adhesion of self-compacting concrete on existing concrete

With the self-compacting concrete(SCC)taken as the new concrete,the experiment research on direct shear behavior of adhesion between existing and new concrete are performed.Based on the test,the effects of specific factors on adhesive shear performance are investigated.These factors are as follows: strength of young concrete,interfacial agents and reinforced bar planting.And normal concrete(NC)is also selected as new concrete in order to compare with selfcompacting concrete.The results show that self-compacting concrete is bonded better with old concrete than normal concrete.The strength of new concrete can influence the bonding of new and existing concrete.As interfacial agent,the mix of cement and fly ash can improve the adhesive shear strength.After planted reinforced bar,the shear strength of new and existing concrete increases greatly.Based on the test result,an expression of shear strength of self-compacting concrete on existing concrete is presented for the reference to the strengthening of concrete structure.