Test Study On The Damage Detection Mineral Admixtures Recycled Concrete Compressive Strength

In the recycled concrete prepared by mixing fly ash and slag powder, form complementary strengths,it not only can effectively conserve natural resources, make full use of waste materials, but also can be good for environment protection and speed up China abandoned the development and utilization of resources, this paper from the Angle of environmental protection and energy saving were made up234pieces of recycled concrete test blocks. Recycled coarse aggregate replace rate for0,20%,40%,60%, and in the recycled coarse aggregate replace rate was60%, on the basis of ore powder and fly ash isometric substitute cement10%,20%,30%, and at the same time in the water cement ratio and other components under the condition of invariable, ore powder and fly ash according to1:1isometric substitute cement10%,20%,30%for the production of strength of concrete test piece C30regeneration, the recycled concrete the damaged tests and microstructure test.First, through the white matter of concrete slump determination test and apparent density test, analysis the mineral admixtures dosage and recycled coarse aggregate replace rate on concrete slump and apparent density effect.Second, adopts the damage detection methods of recycled concrete test piece of test sample blocks measured the rebound value and ultrasonic velocity, and the compressive strength test and measurement test blocks compressive strength value, analysis recycled coarse aggregate replace rate and the mineral admixtures dosage of recycled concrete compressive strength, rebound value and ultrasonic velocity effect, and USES the many kinds of regression way, we establish recycled concrete28d compressive strength the strong rebound method of regression,28d compressive strength strong ultrasonic approach to measure of regression and28d compressive strength of ultrasonic rebound strong measurement of regression, and the return of three strong type are compared and analyzed. Test results show that the double mixing fly ash and fines of recycled concrete compressive strength of the effect is good, mixed with content is20%for optimum content, and that the best effect of ultrasonic rebound, ultrasonic method is the second smallest, and rebound method lowest precision.Again, through the damaged measurement method to detect strong regeneration reinforced concrete column entity the compressive strength, and regeneration concrete test piece of contrast and analysis of three regression between the relations and the correlation coefficient k value, will not damage detection method used in the recycled concrete entity column in actual project.Finally, the mineral admixtures regeneration concrete micro structure analysis, from microcosmic Angle of recycled concrete analysis of mineral admixture affect, of recycled concrete micro structure of the change, double mixing fly ash and kuangfen can effectively improve the internal structure of recycled concrete, so as to improve the regeneration of the concrete compressive strength.