Study Of Revibration And Characteristic Of Concrete Strength

After once vibration of normal concrete (slum≥ 3cm),hole,air bubble,split caused by bleeding and isolation of concrete on interior stone interface will affect ties of concrete and stone,reinforcing steel bar. Revibration will improve the interior structure of concrete and heighten concrete strength. At present, slippery mould construction and the large volume concrete construction are using. From the way of construction we can see upper concrete vibration, underlayer concrete will straight or indirect revibrated. Revibration has important meaning to enhance concrete strength. The paper mostly research on the influence of revibration to concrete.In the thesis, on the base of preceding phenomena, possibility of revibration is put forward and the strength characteristic of revibration concrete are researched. The interior density of concrete is changed which is testified by CTS-45 Ultrasonic wave measuring. The influence factor of the effect of revibration, such as the variety of cement,slum(low model and flowable concrete),the time of revibration are also studied in this paper. The result indicates that the best time of revibration vary from the dfferent kinds of cement , strength grade cement and coagulate time of cement. The effect of revibration for low fluidity concrete is not well, which reduces strength of concrete. The flow concrete effect is better than the model concrete. The best time of revibration for flow concrete can increse strength of concrete in 26 Percent on 28 day and 25 percent on long intensity(120d). through analysed the result of the two kinds of cement, we can see the best time of the revibration in concrete is just from the beginning of bleeding to first coagulation. At last the difference of concrete density is proved . At the same time the cause of strength increased is analysed. In the thesis, the question that based the effect of revibration has not been advanced is put forward.