Experimental Study On Mechanical And Damping Properties Of Modified Recycled Concrete

At present,there are few studies on the mechanical and damping properties of modified recycled coarse aggregate concrete.This paper studies the mechanical and damping properties of modified recycled concrete by adding three kinds of admixtures such as rubber powder,steel fiber and fly ash.The performance and comparative test study found that compared to natural coarse aggregates,the recycled coarse aggregate has low apparent density,large crushing index,and high water absorption.when the replacement rate of recycled aggregate in recycled concrete increases,regeneration occurs.The compressive strength of concrete shows a downward trend and the loss factor shows an upward trend.When the amount of rubber powder increases,the compressive strength of recycled concrete decreases,and its loss factor increases.When the amount of steel fiber increases,recycled concrete increases.The compressive strength is increasing,and its loss factor is also increasing.The compressive strength and loss factor of recycled concrete decreases slightly when blended with 15% fly ash,and after the blend exceeds 20%,it has more Promoted.After the freeze-thaw cycle,the loss factors of the recycled concrete all increase in different ranges.The increase of the loss factor of the recycled concrete is greater than that of the ordinary concrete.The sample with the addition of the admixture has the largest increase in the loss factor.Secondly,the test pieces with fly ash were added.The loss factor of the steel fiber-doped samples changed little before and after freezethaw cycles.