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Lossless concrete for the concrete component provides one of the most practical , the most reliable tool in After the completion of the presumption of damage detection and intensity . Is most commonly used in the existing means of detection rebound method , ultrasonic velocity and ultrasonic and rebound combined method , and these methods have been established norms and the strength curve , but due to the various parts of concrete materials and construction processes impact of specification error of the application of the formula in some places . After this survey research and data analysis , and found that the ultrasound application of existing norms in the region - rebound strength curve when the error is large, the average relative error of 28% . It is necessary to establish the strength curve of the Hohhot region . In this paper, Hohhot used concrete materials , making a total of six different strength grade C20 ~ C45 concrete block , respectively, collected 7d, 14d , 28d , 60d and 90d six age rebound values ??ultrasonic velocity values ??and compressive strength test block . Organize these experimental data analysis , respectively the rebound - strength , ultrasound - strength function model formula . The comparative analysis of the correlation coefficients of the model and accuracy of test data obtained power function formula as recommended formula rebound testing concrete strength of the region , as a linear function of the areas recommended ultrasound - intensity strength curve function . This stage common ultrasound - rebound strength curve to do further research, and , respectively, using a linear function , power function and logarithmic functions fit the relationship between the three physical quantities , after their comparison, the correlation coefficient , error Hohhot regional comprehensive measurement strongly recommended curve formula for power function . The data collected in the post-production of the test block of Hohhot, the regional comprehensive strength curve and norms recommended strength curve analysis test results show that the region the strength curve than the standard curve with high precision .
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