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Site testing of concrete compressive strength in many ways, such as drilled core method, pull out method, indentation method, shooting method, rebound method, ultrasonic method. Among them, the rebound method is through concrete surface hardness springback detection instrument to calculate the compressive strength of concrete method.As concrete rebound hammer cheap, simple structure, reliable performance, easy calibration, repair and maintenance, and testing technology easy to master, the operation is simple, the structure and components without any damage and so on, in the actual engineering testing has been widely used. However, due to rebound method in the course of the operation there are more irregular, arbitrary, improper calculation of the problem, resulting in large errors. Traditionally used to characterize the measurement error of the reliability of the method of measurement is the true value of the relativity, theory, measurement error can not determine the result, making it difficult to adapt to the modern theory of classical error of measurement. The measurement uncertainty is the reliability of the measurement results of the quantitative characterization, the measurement results depends on the availability of a large size of the uncertainty, the measurement results must be accompanied by uncertainty that is complete and meaningful, and therefore to carry out measurement uncertainty in the measurement of concrete compressive strength of resilience among the study has important practical significance.This article through to Foshan a commercial building second frame beams and a residential building three floor rebound data, this paper analyzes research assessment rebound method of testing the compressive strength of concrete method and uncertainty, according to the analysis of the uncertainty of measurement accuracy to puts forward improvement method. The research content mainly includes three parts: (1) the source of uncertainty of analysis. Mainly includes rebound hammer cause standard uncertainty (introduced the strike direction deviation from the standard uncertainty, rebound hammer system performance into uncertainty, etc), the operator factors of uncertainty caused by introducing the reading error (uncertainty, etc.). (2) the factors affecting respectively evaluation caused by uncertainty, and spread of uncertainty of measurement results (concrete compressive strength) integrated uncertainty analysis and evaluation.(3) according to the measurement error factors influence degree of uncertainty, the methods proposed to increase the measurement accuracy.
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